Catholic Encyclopedia 
Moral theology is a branch of theology, the science of  God and Divine 
things. The distinction between natural  and supernatural theology 
rests on a solid foundation.  Natural theology is the science of God 
Himself, in as far  as the human mind can by its own efforts reach a 
definite  conclusion about God and His nature: it is always  designated 
by the adjective natural. Theology, without  any further modification, 
is invariably understood to  mean supernatural theology, that is, the 
science of God  and Divine things, in as far as it is based on  
supernatural Revelation. Its subject-matter embraces not  only God and 
His essence, but also His actions and His  works of salvation and the 
guidance by which we are led  to God, our supernatural end. 
Consequently, it extends  much farther than natural theology; for, 
though the  latter informs us of God's essence and attributes, yet it  
can tell us nothing about His free works of salvation.  The knowledge 
of all these truths is necessary for every  man, at least in its broad 
outlines, and is acquired by  Christian faith. But this is not yet a 
science. The  science of theology demands that the knowledge won  
through faith, be deepened, expanded, and strengthened,  so that the 
articles of faith be understood and defended  by their reasons and be, 
together with their conclusions,  arranged systematically. 
The entire field of theology proper is divided into  dogmatic and moral 
theology, which differ in subject- matter and in method. Dogmatic 
theology has as its end  the scientific discussion and establishment of 
the  doctrines of faith, moral theology of the moral precepts.  The 
precepts of Christian morals are also part of the  doctrines of faith, 
for they were announced or confirmed  by Divine Revelation. The 
subject-matter of dogmatic  theology is those doctrines, which serve to 
enrich the  knowledge necessary or convenient for man, whose  
destination is supernatural. Moral theology, on the other  hand, is 
limited to those doctrines which discuss the  relations of man and his 
free actions to God and his  supernatural end, and propose the means 
instituted by God  for the attainment of that end. Consequently, 
dogmatic  and moral theology are two closely related parts of  
universal theology. Inasmuch as a considerable number of  individual 
doctrines may be claimed by either discipline,  no sharp line of 
demarcation can be drawn between the  subject-matter of dogma and 
morals. In actual practice,  however, a division and limitation must be 
made in  accordance with practical needs. Of a similar nature is  the 
relation between moral theology and ethics. The  subject-matter of 
natural morals or ethics, as contained  in the Decalogue, has been 
included in positive, Divine  Revelation, and hence has passed into 
moral theology.  Nevertheless, the argumentative processes differ in 
the  two sciences, and for this reason a large portion of the  matter 
is disregarded in moral theology and referred to  ethics. For instance, 
the refutation of the false systems  of the modern ethecists is 
generally treated under  ethics, especially because these systems are 
refuted by  arguments drawn not so much from faith, as from reason.  
Only in as far as moral theology requires a defence of  revealed 
doctrines, does it concern itself with false  systems. However, it must 
discuss the various  requirements of the natural law, not only because 
this  law has been confirmed and defined by positive  revelation, but 
also because every violation of it  entails a disturbance of the 
supernatural moral order,  the treatment of which is an essential part 
of moral  theology. 
The field of moral theology, its contents, and the  boundaries which 
separate it from kindred subjects, may  be briefly indicated as 
follows: moral theology includes  everything relating to man's free 
actions and the last,  or supreme, end to be attained through them, as 
far as we  know the same by Divine Revelation; in other words, it  
includes the supernatural end, the rule, or norm, of the  moral order, 
human actions as such, their harmony or  disharmony with the laws of 
the moral order, their  consequences, the Divine aids for their right  
performance. A detailed treatment of these subjects may  be found in 
the second part of St. Thomas's "Summa  theologica", a work still 
unrivaled as a treatise of  moral theology. 
The position of moral theology in universal theology is  briefly 
sketched by St. Thomas in the "Summa theol.", I,  Q. i, a. 7 and Q. ii 
in the proemium and in the prologus  of I-II; likewise by Fr. Suŕrez in 
the proemium of his  commentaries on the I-II of St. Thomas. The 
subject- matter of the entire second part of the "Summa theol."  is, 
man as a free agent. "Man was made after the image of  God, by his 
intellect, his free will, and a certain power  to act of his own 
accord. Hence, after we have spoken of  the pattern, viz. of God, and 
of those things which  proceeded from His Divine power according to His 
will, we  must now turn our attention to His image, that is, man,  
inasmuch as he also is the principle or his actions in  virtue of his 
free will and his power over his own  actions." He includes all this in 
theology, not only  because it is viewed as the object of positive 
Divine  Revelation (I, Q. i, a. 3), but also because God always  is the 
principal object, for "theology treats all things  in their relation to 
God, either in as far as they are  God Himself or are directed towards 
God as their origin  or last end" (I, Q. i, a. 7). "Since it is the 
chief aim  of theology to communicate the knowledge of God, not only  
as He is in Himself but also as the beginning and end of  all things 
and particularly of rational creatures . . . ,  we shall speak first of 
God, secondly of the tendency of  the rational creature towards God", 
etc. (I, Q. ii,  proem.). These words point out the scope and the 
subject- matter of the moral part of theology. Suárez, who  pregnantly 
calls this tendency of the creatures towards  God "the return of the 
creatures to God", shows that  there is no contradiction in designating 
man created  after the image of God, endowed with reason and free will  
and exercising these faculties, as the object of moral  theology, and 
God as the object of entire theology. "If  we are asked to name the 
proximate object of moral  theology, we shall undoubtedly say that it 
is man as a  free agent, who seeks his happiness by his free actions;  
but if we are asked in what respect this object must be  treated 
chiefly, we shall answer that this must be done  with respect to God as 
his last end." 
A detailed account of the wide range of moral theology  may be found in 
the analytical index of Pars Secunda of  St. Thomas's "Summa 
theologica". We must confine  ourselves to a brief summary. The first 
question treats  of man's last end, eternal happiness, Its nature and  
possession. Then follows an examination of human acts in  themselves 
and their various subdivisions, of voluntary  and involuntary acts, of 
the moral uprightness or malice  of both interior and exterior acts and 
their  consequences; the passions in general and in particular;  the 
habits or permanent qualities of the human soul, and  the general 
questions about virtues, vices, and sins.  Under this last title, while 
inquiring into the causes of  sin, the author embodies the doctrine on 
original sin and  its consequences. This portion might, however, be 
with  equal right assigned to dogmatic theology in the stricter  
meaning of the word. Although St. Thomas regards sin  chiefly as a 
transgression of the law, and in particular  of the "lex ćterna" (Q. 
ii, a. 6), still he places the  chapters on the laws after the section 
on sin; because  sin, a free human act like any other human act, is 
first  discussed from the standpoint of its subjective  principles, 
viz. knowledge, will, and the tendency of the  will; only after this 
are the human actions viewed with  regard to their objective or 
exterior principles, and the  exterior principle, by which human 
actions are judged not  merely as human, but as moral actions, either 
morally  good or morally bad, is the law. Since morality is  conceived 
by him as supernatural morality, which exceeds  the nature and the 
faculties of man, Divine grace, the  other exterior principle of man's 
morally good actions,  is discussed after the law. In the exordium to 
Q. xc, St.  Thomas states his division briefly as follows: "The  
exterior principle which moves us to good actions is God;  He instructs 
us by His law and aids us with His grace.  Hence we shall speak first 
of the law, secondly of grace."
The following volume is wholly devoted to the special  questions, in 
the order given by St. Thomas in the  prologue: "After a cursory glance 
at the virtues, vices,  and the moral principles in general, it is 
incumbent on  us to consider the various points in detail. Moral  
discussions, if satisfied with generalities, are of  little value, 
because actions touch particular,  individual things. When there is 
question of morals, we  may consider individual actions in two ways: 
one, by  examining the matter, i. e., by discussing the different  
virtues and vices; another, by inquiring into the various  avocations 
of individuals and their states of life." St.  Thomas then goes on to 
discuss the whole range of moral  theology from both these standpoints. 
First, he closely  scrutinizes the various virtues, keeping in view the  
Divine aids, and the sins and vices opposed to the  respective virtues. 
He examines first the three Divine  virtues which are wholly 
supernatural and embrace the  vast field of charity and its actual 
practice; then he  passes to the cardinal virtues with their auxiliary 
and  allied virtues. The volume concludes with a discussion of  the 
particular states of life in the Church of God,  including those which 
suppose an extraordinary, Divine  guidance. This last part, therefore, 
discusses subjects  which specifically belong to mystical or ascetical  
theology, such as prophecy and extraordinary modes of  prayer, but 
above all the active and the contemplative  life Christian perfection, 
and the religious state in the  Church. The contents of a modern work 
on moral theology,  as, for instance, that of Slater (London, 1909), 
are:  Human acts, conscience, law, sin, the virtues of faith,  hope, 
charity; the precepts of the Decalogue, including a  special treatise 
on justice; the commandments of the  Church; duties attached to 
particular states or offices;  the sacraments, in so far as their 
administration and  reception are a means of moral reform and 
rectitude;  ecclesiastical laws and penalties, only in so far as they  
affect conscience; these laws forming properly the  subject-matter of 
canon law, in so far as they govern and  regulate the Church as an 
organization, Its membership,  ministry, the relations between 
hierarchy, clergy,  religious orders, laity, or of spiritual and 
temporal  authority. 
One circumstance must not be overlooked. Moral theology  considers free 
human actions only in their relation to  the supreme order, and to the 
last and highest end, not  in their relation to the proximate ends 
which man may and  must pursue, as for instance political, social,  
economical. Economics, politics, social science are  separate fields of 
science, not subdivisions of moral  science. Nevertheless, these 
special sciences must also  be guided by morals, and must subordinate 
their specific  principles to those of moral theology, at least so far 
as  not to clash with the latter. Man is one being, and all  his 
actions must finally lead him to his last and highest  end. Therefore, 
various proximate ends must not turn him  from this end, but must be 
made subservient to it and its  attainment. Hence moral theology 
surveys all the  individual relations of man and passes judgment on  
political, economical, social questions, not with regard  to their 
bearings on politics and economy, but with  regard to their influence 
upon a moral life. This is also  the reason why there is hardly another 
science that  touches other spheres so closely as does moral theology,  
and why its sphere is more extensive than that of any  other. This is 
true inasmuch as moral theology has the  eminently practical scope of 
instructing and forming  spiritual directors and confessors, who must 
be familiar  with human conditions in their relation to the moral law,  
and advise persons in every state and situation. 
The manner in which moral theology treats its subject- matter, must be, 
as in theology generally, chiefly  positive, that is, drawing from 
Revelation and  theological sources. Starting from this positive  
foundation, reason also comes into play quite  extensively, especially 
since the whole subject-matter of  natural ethics has been raised to 
the level of  supernatural morals. It is true reason must be illumined  
by supernatural faith, but when illumined its duty is to  explain, 
prove, and defend most of the principles of  moral theology. 
From what has been said it is manifest that the chief  source of moral 
theology is Sacred Scripture and  Tradition together with the teachings 
of the Church.  however, the following points must be observed 
regarding  the Old Testament. Not all precepts contained in it are  
universally valid, as many belong to the ritual and  special law of the 
Jews. These statutes never obliged the  non-Jewish world and have 
simply been abrogated by the  New Covenant, so that now the ritual 
observances proper  are illicit. The Decalogue, however, with the sole 
change  in the law enjoining the celebration of the Sabbath, has  
passed Into the New Covenant a positive Divine  confirmation of the 
natural law, and now constitutes the  principal subject matter of 
Christian morality. Moreover,  we must remember that the Old Covenant 
did not stand on  the high moral level to which Christ elevated the New  
Covenant. Jesus Himself mentions things which were  permitted to the 
Jews "on account of the hardness of  their hearts", but against which 
He applied again the law  at first imposed by God. Hence, not 
everything that was  tolerated in the Old Testament and its writings, 
is  tolerated now; on the contrary, many of the usages  approved and 
established there would be counter to  Christian perfection as 
counseled by Christ. With these  limitations the writings of the Old 
Testament are sources  of moral theology, containing examples of and  
exhortations to heroic virtues, from which the Christian  moralist, 
following in the footsteps of Christ and His  Apostles, may well draw 
superb models of sanctity. 
Apart from Sacred Scripture, the Church recognizes also  Tradition as a 
source of revealed truths, and hence of  Christian morals. It has 
assumed a concrete shape chiefly  in the writings of the Fathers. 
Furthermore, the  decisions of the Church must be regarded as a source,  
since they are based on the Bible and Tradition, they are  the 
proximate source of moral theology, because they  contain the final 
judgment about the meaning of Sacred  Scripture as well as the 
teachings of the Fathers. These  include the long list of condemned 
propositions, which  must be considered as danger signals along the 
boundary  between lawful and illicit, not only when the  condemnation 
has been pronounced by virtue of the highest  Apostolic authority, but 
also when the congregation  instituted by the pope has issued a 
general, doctrinal  decision in questions bearing on morals. What Plus 
IX  wrote concerning the meetings of scholars in Munich in  the year 
1863 may also be applied here: "Since there is  question of that 
subjection which binds all Catholics in  conscience who desire to 
advance the interests of the  Church by devoting themselves to the 
speculative  sciences; let the members of this assembly recall that it  
is not sufficient for Catholic scholars to accept and  esteem the 
above-mentioned dogmas, but that they are also  obliged to submit to 
the decisions of the papal  congregations as well as to those teachings 
which are, by  the constant and universal consent of Catholics, so held  
as theological truths and certain conclusions that the  opposite 
opinion even when not heretical, still deserves  some theological 
censure." If this is true of the  dogmatic doctrines in the strict 
sense of the word, we  might say that it is still more true of moral 
questions,  because for them not only absolute and infallibility  
certain, but also morally certain decisions must be  accounted as 
obligatory norms. 
The words of Plus IX just quoted, point to another source  of 
theological doctrines, and hence of morals, viz., the  universal 
teachings of the Catholic schools. For these  are the channels by which 
the Catholic doctrines on faith  and morals must be transmitted without 
error, and which  have consequently the nature of a source. From the  
unanimous doctrine of the Catholic schools follows  naturally the 
conviction of the universal Church. But  since it is a dogmatic 
principle that the whole Church  cannot err in matters of faith and 
morals, the consent of  the various Catholic schools must offer the 
guarantee of  infallibility in these questions. 
Moral theology, to be complete in every respect, must  accomplish in 
moral questions what dogmatic theology does  in questions pertaining to 
dogma. The latter has to  explain clearly the truths of faith and prove 
them to be  such; it must also, as far as possible, show their  
accordance with reason, defend them against objections,  trace their 
connection with other truths, and, by means  of theological 
argumentation, deduce further truths.  Moral theology must follow the 
same processive questions  of morals. -- It is evident that this cannot 
be done in  all branches of moral theology in such a way as to  exhaust 
the subject, except by a series of monographs. It  would take volumes 
to sketch but the beauty and the  harmony of God's dispositions, which 
transcend the  natural law, but which God enacted in order to elevate  
man to a higher plane and to lead him to his supernatural  end in a 
future life -- and yet all this is embraced in  the subject of 
supernatural morals. Nor is moral theology  confined to the exposition 
of those duties and virtues  which cannot be shirked if man wishes to 
attain his last  end; it includes all virtues, even those which mark 
the  height of Christian perfection, and their practice, not  only in 
the ordinary degree, but also in the ascetical  and mystical life. 
Hence, it is entirely correct to  designate asceticism and mysticism as 
parts of Christian  moral theology, though ordinarily they are treated 
as  distinct sciences. 
The task of the moral theologian is by no means completed  when he has 
explained the questions indicated. Moral  theology, in more than one 
respect, is essentially a  practical science. Its instructions must 
extend to moral  character, moral behaviour, the completion and issue 
of  moral aspirations, so that it can offer a definite norm  for the 
complex situations of human life. For this  purpose, it must examine 
the individual cases which arise  and determine the limits and the 
gravity of the  obligation in each. Particularly those whose office and  
position in the Church demand the cultivation of  theological science, 
and who are called to be the  teachers and counselors, must find in it 
a practical  guide. As jurisprudence must enable the future judge and  
lawyer to administer justice in individual cases, so must  moral 
theology enable the spiritual director or confessor  to decide matters 
of conscience in varied cases of  everyday life; to weigh the 
violations of the natural law  in the balance of Divine justice; it 
must enable the  spiritual guide to distinguish correctly and to advise  
others as to what is sin and what is not, what is  counseled and what 
not, what is good and what is better;  it must provide a scientific 
training for the shepherd of  the flock, so that he can direct all to a 
life of duty  and virtue, warn them against sin and danger, lead from  
good to better those who are endowed with necessary light  and moral 
power, raise up and strengthen those who have  fallen from the moral 
level. Many of these tasks are  assigned to the collateral science of 
pastoral theology;  but this also treats a special part of the duties 
of  moral theology, and falls, therefore, within the scope of  moral 
theology in its widest sense. The purely  theoretical and speculative 
treatment of the moral  questions must be supplemented by casuistry. 
Whether this  should be done separately, that is, whether the subject  
matter should be taken casuistically before or after its  theoretical 
treatment, or whether the method should be at  the same time both 
theoretical and casuistical, is  unimportant for the matter itself; the 
practical  feasibility will decide this point, while for written  works 
on moral theology the special aim of the author  will determine it. 
However, he who teaches or writes  moral theology for the training of 
Catholic priests,  would not do full justice to the end at which he 
must  aim, if he did not unite the casuistical with the  theoretical 
and speculative element. 
What has been said so far, sufficiently outlines the  concept of moral 
theology in its widest sense. Our next  task is to follow up its actual 
formation and  development. 
Moral theology, correctly understood, means the science  of 
supernaturally revealed morals. Hence, they cannot  speak of moral 
theology who reject supernatural  Revelation; the most they can do is 
to discourse on  natural ethics. But to distinguish between moral 
theology  and ethics is sooner or later to admit a science of  ethics 
without God and religion. That this contains an  essential 
contradiction, is plain to everyone who  analyzes the ideas of moral 
rectitude and moral  perversion, or the concept of an absolute duty 
which  forces itself with unrelenting persistency on all who  have 
attained the use of reason. Without God, an absolute  duty is 
inconceivable, because there is nobody to impose  obligation. I cannot 
oblige myself, because I cannot be  my own superior; still less can I 
oblige the whole human  race, and yet I feel myself obliged to many 
things, and  cannot but feel myself absolutely obliged as man, and  
hence cannot but regard all those who share human nature  with me as 
obliged likewise. It is plain then that this  obligation must proceed 
from a higher being who is  superior to all men, not only to those who 
live at  present, but to all who have been and will be, nay, in a  
certain sense even to those who are merely possible, This  superior 
being is the Lord of all, God. It is also plain  that although this 
Supreme lawgiver can be known by  natural reason, neither He nor His 
law can be  sufficiently known without a revelation on His part.  Hence 
if is that moral theology, the study of this Divine  law is actually 
cultivated only by those who faithfully  cling to a Divine Revelation, 
and by the sects which  sever their connection with the Church, only as 
long as  they retain the belief in a supernatural Revelation  through 
Jesus Christ. 
Wherever Protestantism has thrown this belief overboard,  there the 
study of moral theology as a science has  suffered shipwreck. Today it 
would be merely lost labour  to look for an advancement of it on the 
part of a non- Catholic denomination. In the seventeenth and eighteenth  
centuries there were still men to be found who made an  attempt at it. 
J. A. Dorner states in Herzog, "Real- Encyklopädie", IV, 364 sqq. (s. 
v. "Ethik"), that  prominent Protestant writers upholding "theological  
morals" have grown very scarce since the eighteenth  century. However, 
this is not quite correct. Of those who  still cling to a positive 
Protestantism, we may name  Martensen, who recently entered the lists 
with deep  conviction for "Christian Ethics"; the same, though in  his 
own peculiar manner, is done by Lemme in his  "Christliche Ethik" 
(1905); both attribute to it a scope  wider and objectively other than 
that of natural ethics.  A few names from the seventeenth and 
eighteenth centuries  may here suffice: Hugo Grotius (d. 1645), 
Pufendorf (d.  1694) and Christian Thomasius (d. 1728), all see the  
difference between theological and natural morals in that  the former 
is also positive, i. e. Divinely revealed, but  with the same subject 
matter as the latter. This last  assertion could spring only from the 
Protestant view  which has staked its all on the "fides fiducialis"; 
but  it can hardly acknowledge a range of duties widened by  Christ and 
Christianity. Other writers of a "theologia  moralis" based on this 
"fides fiducialis", are Buddeus,  Chr. A. Crusius, and Jerem. Fr. 
Reuss. A logical result  of Kantianism was the denial of the very 
possibility of  moral theology, since Kant had made autonomous reason 
the  only source of obligation. On this point Dorner says  (loc. cit.): 
" It is true that the autonomy and the  autocracy of the moral being 
separates morals and  religion"; he would have been nearer the mark, 
had he  said: "they destroy all morals". Generally speaking the  modern 
Liberal Protestants hardly know any other than  autonomous morals; even 
when they do speak of "religious"  morals, they find its last 
explanation in man, religion,  and God or Divine Revelation being taken 
in their  Modernistic sense, that is subjective notions of whose  
objective value we have no knowledge and no certainty. 
This being the case, there remains only one question to  be discussed: 
What has been the actual development and  method of moral theology in 
the Church? and here we must  first of all remember that the Church is 
not an  educational institution or a school for the advancement  of the 
sciences. True, she esteems and promotes the  sciences, especially 
theology, and scientific schools are  founded by her; but this is not 
her only, or even her  chief task. She is the authoritative 
institution, founded  by Christ for the salvation of mankind; she 
speaks with  power and authority to the whole human race, to all  
nations, to all classes of society, to every age,  communicates to them 
the doctrine of salvation  unadulterated and. offers them her aids. It 
is her  mission to urge upon educated and uneducated persons  alike the 
acceptance of truth, without regard to its  scientific study and 
establishment. After this has been  accepted on faith, she also 
promotes and urges, according  to times and circumstances, the 
scientific investigation  of the truth, but she retains supervision 
over it and  stands above all scientific aspirations and labours. As a  
result, we see the subject matter of moral theology,  though laid down 
and positively communicated by the  Church, treated differently by 
ecclesiastical writers  according to the requirements of times and 
In the first years of the early Church, when the Divine  seed, 
nourished by the blood of the martyrs, was seen to  sprout in spite of 
the chilling frosts of persecution,  when, to the amazement of the 
hostile world, it grew into  a mighty tree of heavenly plantation, 
there was hardly  leisure for the scientific study of Christian 
doctrine.  Hence morals were at first treated in a popular,  parenetic 
form. Throughout the Patristic period, hardly  any other method for 
moral questions was in vogue, though  this method might consist now in 
a concise exposition,  now in a more detailed discussion of individual 
virtues  and duties. One of the earliest works of Christian  tradition, 
if not the earliest after the Sacred  Scripture, the "Didache" or 
"Teaching of the Apostles",  is chiefly of a moral-theological nature. 
It Is hardly  more than a code of laws, an enlarged decalogue, to which  
are added the principal duties arising from the Divine  institution of 
the means of salvation and from the  Apostolic institutions of a common 
worship -- in this  respect valuable for dogmatic theology in its 
narrow  sense. The "Pastor" of Hermas, composed a little later,  is of 
a moral character, that is, it contains an  ascetical exhortation to 
Christian morality and to  serious penance if one should have relapsed 
into sin. 
There exists a long series of occasional writings bearing  on moral 
theology, from the first period of the Christian  era; their purpose 
was either to recommend a certain  virtue, or to exhort the faithful in 
general for certain  times and circumstances. Thus, from Tertullian (d. 
about  240) we have: "De spectaculis", "De idololatria", "De  corona 
militis", "De patientia", "De oratione", "De  pœnitentia", "Ad uxorem", 
not to take into consideration  the works which he wrote after his 
defection to Montanism  and which are indeed of interest for the 
history of  Christian morals, but cannot serve as guides in it. Of  
Origen (d. 254) we still possess two minor works which  bear on our 
question, viz., "Demartyrio", parenetic in  character, and "De 
oratione", moral and dogmatic in  content; the latter meets the 
objections which are  advanced or rather reiterated even today against 
the  efficacy of prayer. Occasional writings and monographs  are 
offered to us in the precious works of St. Cyprian  (d. 258); among the 
former must be numbered: "De  mortalitate" and "De martyrio", in a 
certain sense also  "Delapsis", though it bears rather a disciplinary 
and  judicial character; to the latter class belong: "De  habitu 
virginum", "De oratione", "De opere et  eleemosynis", "De bono 
patientić", and "De zelo et  livore". A clearer title to be classed 
among moral- theological books seems to belong to an earlier work, the  
"Pćdagogus" of Clement of Alexandria (d. about 217). It  is a detailed 
account of a genuine Christian's daily  life, in which ordinary and 
everyday actions are measured  by the standard of supernatural 
morality. The same author  touches upon Christian morals also in his 
other works,  particularly in the "'Stromata"; but this work is  
principally written from the apologetic standpoint, since  it was 
intended to vindicate the entire Christian  doctrine, both faith and 
morals, against pagan and Jewish  philosophies. 
In subsequent years, when the persecutions ceased, and  patristic 
literature began to flourish, we find not only  exegetical writings and 
apologies written to defend  Christian doctrine against various 
heresies, but also  numerous moral-theological works, principally 
sermons,  homilies, and monographs. First of these are the orations  of 
St. Gregory of Nazianzus (d. 391), of St. Gregory of  Nyssa (d. 395), 
of St. John Chrysostom (d. 406), of St.  Augustine (d. 430), and above 
all the "Catecheses" of St.  Cyril of Jerusalem (d. 386). Of St. John 
Chrysostom we  have "De sacerdotio"; of St. Augustine, "Confessiones",  
"Soliloquia", "De cathechizandis rudibus", "De  patientia", "De 
continentia", "De bono coniugali", "De  adulterinis coniugiis", "De 
sancta virginitate", "De bono  viduitatis", "De mendacio", "De cura pro 
mortuis  gerenda", so that the titles alone suffice to give an  
intimation of the wealth of subjects discussed with no  less unction 
than originality and depth of thought. A  separate treatment of the 
supernatural morality of  Christians was attempted by St. Ambrose (d. 
397) in his  books "De officiis", a work which, imitating Cicero's "De  
officiis", forms a Christian counterpart of the pagan's  purely natural 
discussions. A work of an entirely  different stamp and of larger 
proportions is the  "Expositio in Job, seu moralium lib. XXV", of 
Gregory the  Great (d. 604). It is not a systematic arrangement of the  
various Christian duties, but a collection of moral  instructions and 
exhortations based on the Book of Job;  Alzog (Handbuch der Patrologie, 
92) calls it a "fairly  complete repertory of morals". More systematic 
is his  work "De cura pastorali" which was intended primarily for  the 
pastor and which is considered even today a classical  work in pastoral 
Having broadly outlined the general progress of moral  theology during 
the Patristic era proper, we must  supplement it by detailing the 
development of a very  special branch of moral theology and its 
practical  application. For moral theology must necessarily assume a  
peculiar form when its purpose is restricted to the  administration of 
the Sacrament of Penance. The chief  result to be attained was a clear 
notion of the various  sins and their species, of their relative 
grievousness  and importance, and of the penance to be imposed for  
them. In order to ensure uniform procedure, it was  necessary for 
ecclesiastical superiors to lay down more  detailed directions; this 
they did either of their own  accord or in answer to inquiries. 
Writings of this kind  are the pastoral or canonical letters of St. 
Cyprian, St.  Peter of Alexandria, St. Basil of Cappadocia, and St.  
Gregory of Nyssa; the decretals and synodal letters of a  number of 
popes, as Siricius, Innocent, Celestine, Leo I,  etc.; canons of 
several œcumenical councils. These  decrees were collected at an early 
date and used by the  bishops and priests as a norm in distinguishing 
sins and  in imposing ecclesiastical penance for them. 
The ascendancy of the so-called "penitential books" dated  from the 
seventh century, when a change took place in the  practice of 
ecclesiastical penance. Till then it had been  a time-honoured law in 
the Church that the three capital  crimes: apostasy, murder, and 
adultery, were to be atoned  for by an accurately determined penance, 
which was public  at least for public sins. This atonement, which 
consisted  chiefly in severe fasts and public, humiliating  practices, 
was accompanied by various religious  ceremonies under the strict 
supervision of the Church; it  included four distinct stations or 
classes of penitents  and at times lasted from fifteen to twenty years. 
At an  early period, however, the capital sins mentioned above  were 
divided into sections, according as the  circumstances were either 
aggravating or attenuating;,  and a correspondingly longer or shorter 
period of penance  was set down for them. When in the course of 
centuries,  entire nations, uncivilized and dominated by fierce  
passions, were received into the bosom of the Church, and  when, as a 
result, heinous crimes began to multiply, many  offences, akin to those 
mentioned above, were included  among sins which were subject to 
canonical penances,  while for others, especially for secret sins, the 
priest  determined the penance, its duration and mode, by the  canons. 
The seventh century brought with It a relaxation,  not indeed in 
canonical penance, but in the  ecclesiastical control; on the other 
hand, there was an  increase in the number of crimes which demanded a 
fixed  penance if discipline was to be maintained; besides, many  
hereditary rights of a particular nature, which had led  to a certain 
mitigation of the universal norm of penance,  had to be taken into 
consideration; substitutes and so- called redemptiones, which consisted 
in pecuniary  donations to the poor or to public utilities, gradually  
gained entrance and vogue; all this necessitated the  drawing up of 
comprehensive lists of the various crimes  and of the penances to be 
imposed for them, so that a  certain uniformity among confessors might 
be reached as  to the treatment of penitents and the administration of  
the sacraments. 
There appeared a number of "penitential books" Some of  them, bearing 
the sanction of the Church, closely  followed the ancient canonical 
decrees of the popes and  the councils, and the approved statutes of 
St. Basil, St.  Gregory of Nyssa, and others; others were merely 
private  works, which, recommended by the renown of their authors,  
found a wide circulation, others again went too far in  their decisions 
and hence constrained ecclesiastical  superiors either to reprehend or 
condemn them. A more  detailed account of these works will be found in 
another  article. 
These books were not written for a scientific, but for a  practical 
juridical purpose. Nor do they mark an advance  in the science of moral 
theology, but rather a standing- still, nay, even a decadence. Those 
centuries of  migrations, of social and political upheavals, offered a  
soil little adapted for a successful cultivation of the  sciences, and 
though in the ninth century a fresh attempt  was made to raise 
scientific studies to a higher level,  still the work of the subsequent 
centuries consisted  rather in collecting and renewing treasures of 
former  centuries than in adding to them. This is true of moral- 
theological questions, no less than of other scientific  branches. From 
this stagnation theology in general and  moral theology in particular 
rose again to new life  towards the end of the twelfth and the 
beginning of the  thirteenth century. A new current of healthy 
development  was noticeable in moral theology and that in two  
directions: one in the new strength infused into the  practice of the 
confessors, the other in renewed vigour  given to the speculative 
With the gradual dying out of the public penances, the  "penitential 
books" lost their importance more and more.  The confessors grew less 
concerned about the exact  measure of penances than about the essential 
object of  the sacrament, which is the reconciliation of the sinner  
with God. Besides, the “penitential books" were by far  too defective 
for teaching confessors how to judge about  the various sins, their 
consequences and remedies. In  order to meet this need, St. Raymond of 
Penafort wrote  towards the year 1235 the “Summa de pœnitentia et  
matrimonio". Like his famous collection of decretals, it  is a 
repertory of canons on various matters, i. e.  important passages from 
the Fathers, councils, and papal  decisions. More immediately adapted 
for actual use was  the "Summa de casibus conscientić", which was 
written  about 1317 by an unknown member of the Order of St.  Francis 
at Asti in Upper Italy, and which is, therefore,  known as "Summa 
Astensana" or "Summa Astensis". Its eight  books cover the whole 
subject matter of moral theology  and the canonical decrees, both 
indispensable for the  pastor and confessor: Book I, the Divine 
commandments;  II, virtues and vices; III, contracts and wills; IV-VI,  
sacraments, except matrimony; VII, ecclesiastical  censures; VIII, 
matrimony. The fourteenth and fifteenth  centuries produced a number of 
similar summœ for  confessors; all of them, however, discarded the  
arrangement in books and chapters, and adopted the  alphabetical order. 
Their value is, of course, widely  different. The following are the 
most important and most  popular among them: The "Summa confessorum" of 
the  Dominican Johannes of Freiburg (d. 1314) which was  published a 
few years previous to the "Summa Astensis";  its high reputation and 
wide circulation was due to its  revision by another member of the 
Dominican Order,  Bartholomćus of Pisa (d. 1347) who arranged it  
alphabetically and supplemented its canonical parts; it  is commonly 
known as the "Summa Pisana". This work served  as the foundation for 
the "Summa. angelica", a clear and  concise treatise, composed about 
1476 by the Franciscan  Angelus Cerletus, called "Angelus a Clavasio" 
after his  native city, Chiavasso. Its great popularity is attested  by 
the fact that it went through at least thirty-one  editions from 1476 
to 1520. A like popularity was enjoyed  by the "Summa casuum" of the 
Franciscan, J. B. Trovamala,  which appeared a few years later (1484) 
and, after being  revised by the author himself, in 1495, bore the 
title of  "Summa rosella". One of the last and most renowned of  these 
summœ was probably the "Summa Silvestrina" of the  Dominican Silvester 
Prierias (d. 1523), after which moral  theology began to be treated in 
a different manner. The  summœ here mentioned, being exclusively 
written for the  practical use of confessors, did not spurn the more  
elementary form; but they represented the results of a  thorough, 
scientific study, which produced not only  writings of this kind, but 
also other systematic works of  a profound scholarship. 
The twelfth century witnessed a busy activity in  speculative theology, 
which centered about the cathedral  and monastic schools. These 
produced men like Hugh and  Richard of St. Victor, and especially 
Hugh's pupil, Peter  the Lombard, called the Master of the Sentences, 
who  flourished in the cathedral school of Paris towards the  middle of 
the century, and whose "Libri sententiarum"  served for several 
centuries as the standard text-book in  theological lecture-halls. In 
those days, however,. when  dangerous heresies against the fundamental 
dogmas and  mysteries of the Christian faith began to appear, the  
moral part of the Christian doctrine received scant  treatment; Peter 
the Lombard incidentally discusses a few  moral questions, as e. g., 
about sin, while speaking of  creation and the original state of man, 
or more in  particular, while treating of original sin. Other  
questions, e. g., about the freedom of our actions and  the nature of 
human actions in general, are answered in  the doctrine on Christ, 
where he discusses the knowledge  and the will of Christ. Even the 
renowned commentator of  the "Sentences", Alexander of Hales, O. Min., 
does not  yet seriously enter into Christian morals. The work of  
constructing moral theology as a speculative science was  at last 
undertaken and completed by that great luminary  of theology, St. 
Thomas of Aquin, to whose "Summa  theologica" we referred above. Aside 
from this  masterpiece, of which the second part and portions of the  
third pertain to morals, there are several minor works  extant which 
bear a moral and ascetical character; the  last-named branch was 
cultivated with extraordinary skill  by St. Bonaventure of the 
Franciscan Order, though he did  not equal the systematic genius of St. 
This and the subsequent centuries produced a number of  prominent 
theologians, some of whom contested various  doctrines of Aquinas, as 
Duns Scotus and his adherents,  while others followed in his footsteps 
and wrote  commentaries on his works, as Aegidius Romanus and  
Capreolus. Nevertheless, purely moral-theological  questions were 
rarely made the subject of controversy  during this time; a new epoch 
in the method of moral  theology did not dawn until after the Council 
of Trent.  However, there are two extremely fertile writers of the  
fifteenth century who not only exerted a powerful  influence on the 
advancement of theology but raised the  standard of practical life. 
They are Dionysius the  Carthusian and St. Antoninus, Bishop of 
Florence. The  former is well known for his ascetical works, while the  
latter devoted himself to the practice of the  confessional and the 
ordinary work of the pastor. His  "Summa theologica" belongs specially 
to our subject. It  went through several editions, and A. Ballerini's  
revision of it, which appeared in 1740 at Florence,  contains four 
folios. The third volume treats chiefly of  ecclesiastical law; it 
discusses at great length the  legal position of the Church and its 
penal code. A few  chapters of the first volume are devoted to the  
psychological side of man and his actions. The remainder  of the whole 
work is a commentary, from the purely moral  standpoint, on the second 
part of St. Thomas's "Summa  theologica", to which it constantly 
refers. It is not a  mere theoretical explanation, but is so replete 
with  juridical and casuistical details that it may be called  an 
inexhaustible fountain for manuals of casuistry. How  highly the 
practical wisdom of Antoninus was esteemed  even during his lifetime is 
attested by the surname  "Antoninus consiliorum", Antoninus of good 
counsel, given  to him in the Roman Breviary. 
A new life was breathed into the Catholic Church by the  Council of 
Trent. Reformation of morals gave a fresh  impetus to theological 
science. These had gradually  fallen from the high level to which they 
had risen at the  time of St. Thomas; the desire of solid advancement 
had  frequently given place to seeking after clever  argumentations on 
unimportant questions. The sixteenth  century witnessed a complete 
change. Even before the  council convened, there were eminent scholars 
of a  serious turn of mind as Thomas of Vio (usually called  
Cajetanus), Victoria, and the two Sotos, all men whose  solid knowledge 
of theology proved of immense benefit to  the Council itself. Their 
example was followed by a long  series of excellent scholars, 
especially Dominicans and  members of the newly-founded Society of 
Jesus. It was  above all the systematic side of moral theology which 
was  now taken up with renewed zeal. In former centuries,  Peter the 
Lombard's "Sentences" had been the universal  text-book, and more 
prominent theological works of  subsequent ages professed to be nothing 
else than  commentaries upon them; henceforth, however, the "Summa  
theologica" of St. Thomas was followed as guide in  theology and a 
large number of the best theological  works, written after the Council 
of Trent, were entitled  "Commentarii in Summam Sti. Thomae”. The 
natural result  was a more extensive treatment of moral questions, 
since  these constituted by far the largest portion of St.  Thomas's 
"Summa". Among the earliest classical works of  this kind is the 
"Commentariorum theologicorum tomi  quattuor" of Gregory of Valentia 
(q.v.). It is well  thought out and shows great accuracy; vols. III and 
IV  contain the explanation of the "Prima Secundae" and the  “Secunda 
Secundae” of St. Thomas. This work was succeeded,  at the end of the 
sixteenth and the beginning of the  seventeenth century, by a number of 
similar commentaries;  among them stand out most prominently those of 
Gabriel  Vásquez", Lessius, Suárez, Becanus, and the works of  Thomas 
Sanchez "In decalogum" as well as "Consilia  moralia", which are more 
casuistical in their method; the  commentaries of Dominic Bánez, which 
had appeared some  time before; and those of Medina (see MEDINA,  
Prominent among all those mentioned is Francis Suárez, S.  J., in whose 
voluminous works the principle questions of  the "Seounda" of St. 
Thomas are developed with great  accuracy and a wealth of positive 
knowledge. Almost every  question is searchingly examined, and brought 
nearer its  final solution; the most varied opinions of former  
theologians are extensively discussed, subjected to a  close scrutiny, 
and the final decision is given with  great circumspection, moderation, 
and modesty. A large  folio treats the fundamental questions of moral 
theology  in general: 
(1) De fine et beatitudine; 
(2) De voluntario et involuntario, et de actibus humanis; 
(3) De bonitate et malitia humanorum actuum; 
(4) De passionibus et vitiis. 
Another volume treats of "Laws": several folio volumes  are devoted to 
treatises which do indeed belong to  morals, but which are inseparably 
connected with other  strictly dogmatic questions about God and His 
attributes,  viz., "De gratia divina"; they are today assigned  
everywhere to dogma proper; a third series gives the  entire doctrine 
of the sacraments (with the exception of  matrimony) from their 
dogmatic and moral side. Not all of  the various virtues were examined 
by Suárez; besides the  treatise on the theological virtues, we possess 
only that  on the virtue of religion. But if any of Suárez's works  may 
be called classical it is the last-named, which  discusses in four 
volumes the whole subject "De  religione" Within the whole range of 
"religio", including  its notion and relative position, its various 
acts and  practices, as prayers, vows, oaths, etc., the sins  against 
it, there can hardly be found a dogmatic or  casuistic question that 
has not been either solved or  whose solution has not at least been 
attempted. Of the  last two volumes one treats of religious orders in  
general, the other of the "Institute" of the Society of  Jesus. 
In the course of the seventeenth and eighteenth century,  there 
appeared a number of similar, though conciser,  works which treat 
moral-theological questions as a part  of universal theology with the 
genuine spirit of  Scholastic science. There are those of Tanner, 
Coninck,  Platel, Gotti, Billuart, and many others, the mere  
enumeration of whom would lead us too far afield. We  must, however, 
mention one to whom nobody can deny the  honour of having advanced both 
speculative and practical  theology, and especially practical morals, 
John de Lugo.  Endowed with uncommon, speculative genius and clear,  
practical judgment, he in many instances pointed out  entirely new 
paths towards the solution of moral  questions. Speaking of his moral 
theology, St. Alphonsus  styles him "by all odds leader after St. 
Thomas". The  works that have come down to us are: "De fide", "De  
Incarnatione", "De justitia et jure", "De sacramentis",  viz., "De 
sacramentis in genere", "De baptismo et  eucharistia", and "De 
pœnitentia". It is above all the  volume "De pœnitentia" which, through 
its sixteenth  disputation, has become the classical handbook for  
casuistical moral theology and particularly for the  specific 
distinction of sins; to the same subject belong  the posthumous 
"Responsa moralia", a collection of  answers given by de Lugo in 
complicated cases of  conscience. This is not the place to point out 
his  eminence as a dogmatist; suffice it to say that many far- reaching 
questions receive original solutions, which,  though not universally 
accepted, have yet shed  considerable light on these subjects. 
The method which Lugo applies to moral theological  questions, may well 
be called mixed, that is, it is both  speculative and casuistical. Such 
works of a mixed  character now grow common, they treat the whole 
subject- matter of moral theology, in as far as it is serviceable  for 
the confessor and the pastor, in this mixed manner,  though they insist 
more on casuistry than did Lugo. A  type of this kind is the "Theologia 
moralis" of Paul  Laymann (d. 1635); in this category may also be 
numbered  the "Theologia decalogalis" and "Theologia sacramentalis"  of 
Sporer (d. 1683), the "Conferentić" of Elbel (d.  1756), and the 
"Theologia moralis" of Reuter (d. 1762).  Almost numberless are the 
manuals for confessors, written  in a simple casuistical form, though 
even these justify  their conclusions by internal reasons after  
legitimatizing them by an appeal to external authority.  They are not 
infrequently the fruit of thorough,  speculative knowledge and 
extensive reading. One of the  most solid is probably the "Manuale 
confessariorum et  pœnitentium" of Azpilcueta (1494-1586), the great  
canonist, commonly known as "Doctor Navarrus";  furthermore, the 
"Instructio sacerdotum" or "Summa casuum  conscientić" of Cardinal 
Tolet (d. 1596), which was  highly recommended by St. Francis of Sales. 
One other  work must also be mentioned, viz., the so-called "Medulla  
theologić moralis" of Hermann Busenbaum (d. 1688), which  has become 
famous on account of its very extensive use  (forty editions in less 
than twenty years during the  lifetime of the author) and the number of 
its  commentators. Among these are included Claude Lacroix,  whose 
moral theology is considered as one of the most  valuable of the 
eighteenth century, and St. Alphonsus  Liguori, with whom, however, an 
entirely new epoch of  moral theology commences. 
Before entering upon this new phase, let us glance at the  development 
of the so-called systems of morals and the  controversies which sprang 
up among Catholic scholars, as  well as at the casuistical method of 
treating moral  theology in general. For it is precisely the casuistry 
of  moral theology around which these controversies centre,  and which 
has experienced severe attacks in our own day.  These attacks were for 
the most part confined to Germany.  The champions of the adversaries 
are J. B. Hirscher (d.  1865), Döllinger, Reusch, and a group of 
Catholic  scholars who, in the years 1901 and 1902, demanded a  "reform 
of Catholic moral theology", though all were not  moved by the same 
spirit. In Hirscher it was the zeal for  a supposedly good cause, 
though he was implicated in  theological errors; Döllinger and Reusch 
attempted to  cover their defection from the Church and their refusal  
to acknowledge the papal infallibility by holding up to  the ridicule 
of the world ecclesiastical conditions and  affairs which they thought 
militated against that  infallibility; the latest phase of this 
opposition is  mainly the result of misunderstandings. In order to  
elucidate the accusations brought against casuistry, we  use the wholly 
unjustifiable criticism which Hirscher  launched against Scholastic 
theology in general in his  work of 1832, "On the Relation between the 
Gospel and  Theological Scholasticism"; it is quoted approvingly by  
Döllinger and Reusch (Moralstreitigkeiten, 13 sqq.): 
(1) "Instead of penetrating into the spirit which makes  virtue what it 
is and underlies everything that is good  in this world, in other 
words, instead of beginning with  the one indivisible nature of all 
goodness, they begin  with the material of the various moral precepts 
and  prohibitions without adverting to where these originate,  on what 
foundation they rest, and what is their life- giving principle." This 
means that Scholastics and  casuists know only individual things, see 
nothing  universal and uniform in the virtues and duties. 
(2) "Instead of deriving these precepts and prohibitions  from the one, 
individual essence of all goodness and  thereby creating certainty in 
the moral judgments of  their audience, they, rejecting principles, 
string  'shalt' to 'shalt', provide them with innumerable  statutes and 
clauses, confuse and oppress the hearer by  the overflowing measure of 
duties, half-duties, non- duties." In other words, the Scholastics 
oppress and  confuse by an unnecessary multiplication of duties and  
(3) "It is more in accordance with the spirit of Mosaism  than with 
that of Christianity when Christian morality is  treated less as a 
doctrine of virtues than of laws and  duties, and when by adding 
commandment to commandment,  prohibition to prohibition, it gives us a 
full and shaken  measure of moral rules instead of building up on the  
Christian spirit, deriving everything from it and  pointing out all 
particular virtues in its light." Or  briefly, casuistry promotes 
exterior sanctimoniousness  without the interior spirit. 
(4) "Those who treat morals from the standpoint of  casuistry, assign 
an important part to the distinction  between grave and light laws, 
grave and light duties,  serious and slight transgressions, mortal and 
venial  sins. . . . Now, the distinction between grievous and  venial 
sins is not without a solid foundation, and if it  is chiefly based on 
the different qualities of the will,  and if, besides, the various 
degrees of goodness and  malice are measured by the presence, e. g., of 
a purely  good and strong will, of one less pure and less strong,  of a 
weak, inert, impure, malicious, perverted will, then  nobody will raise 
his voice against it. But it is wholly  different when the distinction 
between mortal and venial  sins is taken objectively, and based on the 
gravity and  lightness of the commandments. . . . Such a distinction  
between mortal and venial sins, founded on the material  differences of 
the commandments and the prohibitions, is  a source of torment and 
anxiety for many. . . . True  morality cannot be advanced through such 
an anxiety. . .  . The mass of the people will derive only this one 
profit  from such a method: many will refrain from what is  forbidden 
under pain of mortal sin and will do what is  commanded under the same 
penalty, but they will care  little for what is commanded or forbidden 
under pain of  venial sin only; on the contrary they will seek a  
compensation in the latter for what they sacrificed to  the grave 
commandments. But can we call the lives of such  men Christian?" In 
other words, casuistry falsifies the  consciences by distinguishing 
objectively between mortal  and venial sins, leads to a contempt of the 
latter, and  renders a genuinely Christian life impossible. 
It is not difficult to refute all these accusations. One  glance at the 
"Summa theologica" of St. Thomas will prove  how incorrect is the first 
charge that Scholasticism and  casuistry know only individual good acts 
and individual  virtues, without inquiring into the foundation common 
to  all virtues. Before treating the individual virtues and  the 
individual duties, St. Thomas gives us a whole volume  of discussions 
of a general nature, of which we may note  the profound speculations on 
the last end, the goodness  and malice of human actions, the eternal 
The second accusation, that the Scholastic casuistry  confuses the mind 
by its mass of duties and non-duties,  can only mean that the 
Scholastic casuistry sets these up  arbitrarily and contrary to truth. 
The complaint can only  refer to those works and lectures which aim at 
the  instruction of the clergy, pastors, and confessors. The  reader or 
hearer who is confused or oppressed by this  "mass of duties etc." 
shows by this very fact that he has  not the talent necessary for the 
office of confessor or  spiritual guide, that he should therefore 
choose another  vocation. 
The third charge, directed against Judaical hypocrisy  which neglects 
the fostering of the interior life, is  refuted by every work on 
casuistry, however meagre, for  every one of them states most 
emphatically that, without  the state of grace and a good intention, 
all external  works, no matter how difficult and heroic, are valueless  
in the sight of God. Can the necessity of the internal  spirit be 
brought out more clearly? And even if, in some  cases, the external 
fulfillment of a certain work is laid  down as the minimum demanded by 
God or the Church,  without which the Christian would incur eternal  
damnation, yet this is not banishing the internal spirit,  but 
designating the external fulfillment as the low-water  mark of 
Lastly, the fourth charge springs from a very grave  theological error. 
There can be no doubt that, in judging  the heinousness of sin and in 
distinguishing between  mortal and venial sins, the subjective element 
must be  taken into consideration, However, every compendium of  moral 
theology, no matter how casuistical, meets this  requirement. Every 
manual distinguishes sins which arise  from ignorance, weakness, 
malice, without, however,  labelling all sins of weakness as venial 
sins, or all  sins of malice as mortal sins; for there are surely minor  
acts of malice which cannot be said to cause the death of  the soul. 
Every manual also takes cognizance of sins  which are committed without 
sufficient deliberation,  knowledge, or freedom: all these, even though 
the matter  be grave, are counted as venial sins. On the other hand,  
every manual recognizes venial and grievous sins which  are such by the 
gravity of the matter alone. Or who  would, abstracting from everything 
else, put a jocose lie  on a par with the denial of faith? But even in 
these  sins, mortal or venial according to their object, the  casuists 
lay stress on the personal dispositions in which  the sin was actually 
committed. Hence, their universal  principle: the result of a 
subjectively erroneous  conscience may be that an action which is in 
itself only  venial, becomes a mortal sin, and vice versa, that an  
action which is in itself mortally sinful, that is,  constitutes a 
grave violation of the moral law, may be  only a venial sin. 
Nevertheless, all theologians, also  casuists, consider a correct 
conscience a great boon and  hence endeavour, by their casuistic 
discussions, to  contribute towards the formation of correct 
consciences,  so that the subjective estimate of the morality of  
certain actions may coincide, as far as possible, with  the objective 
norm of morality. 
When, lastly, various opponents of the casuistical method  object that 
the moralist occupies himself exclusively  with sins and their 
analysis, with the "dark side" of  human life, let them remember that 
it is physically  impossible to say everything in one breath, that, 
just as  in many other arts and sciences, a division of labour may  
also be advantageous for the science of moral theology,  that the 
particular purpose of manuals and lectures may  be limited to the 
education of skilled confessors and  that this purpose may very well be 
fulfilled by centering  attention on the dark side of human life. 
Nevertheless,  it must be granted that this cannot be the only purpose  
of moral theology: a thorough discussion of all Christian  virtues and 
the means of acquiring them is Indispensable.  If at any time this part 
of moral theology should be  pushed to the background, moral theology 
would become  one-sided and would need a revision, not by cutting down  
casuistry, but by devoting more time and energy to the  doctrine of 
virtues in their scientific, parenetical, and  ascetical aspect. 
In all these branches of moral theology, a great advance  was 
noticeable at the time of the Council of Trent. That  more stress was 
laid on casuistry in particular, finds  its explanation in the growing 
frequency of sacramental  confession. This is freely conceded by our 
adversaries.  Döllinger and Reusch say (op. cit., 19 sqq.): "The fact  
that casuistry underwent a further development after the  sixteenth 
century, is connected with further changes in  the penitential 
discipline. From that time on the custom  prevailed of approaching the 
confessional more  frequently, regularly before Communion, of 
confessing not  only grievous, but also venial sins, and of asking the  
confessor's advice for all troubles of the spiritual  life, so that the 
confessor became more and more a  spiritual father and guide." The 
confessor needed this  schooling and scientific training, which alone 
could  enable him to give correct decisions in complex cases of  human 
life, to form a correct estimate of moral goodness  or defect, duty or 
violation of duty, virtue or vice.  Now, it was inevitable that the 
confessor should meet  cases where the existence or exact measure of 
the  obligation remained obscure even after careful  examination, where 
the moralist was therefore confronted  by the question what the final 
decision in these cases  should be: whether one was obliged to consider 
oneself  bound when the duty was obscure and doubtful, or how one  
could remove this doubt and arrive at the definite  conclusion that 
there was no strict obligation. That the  former could not be the case, 
but that an obligation, to  exist, must first be proved, had always 
been known and  had been variously expressed in practical rules: "In  
dubiis benigniora sequenda", "odiosa sunt restringenda",  etc. The 
basic principle, however, for solving such  dubious cases and attaining 
the certitude necessary for  the morality of an action was not always 
kept clearly in  view. To establish this universal principle, was  
equivalent to establishing a moral system; and the  various systems 
were distinguished by the principle to  which each adhered. 
The history of Probabilism is given under this title,  suffice it to 
say here that from the middle of the  seventeenth century when the 
violent discussion of this  question begins, the development of moral 
theology  coincides with that of Probabilism and of other  
Probabilistic systems; although these systems touch only  a small 
portion of morals and of moral truths and nothing  is farther from the 
truth than the opinion, so wide- spread among the adversaries of 
Catholic morals, that  Probabilism gave a new shape and a new spirit to 
the  whole of moral theology. Probabilism and the other  systems of 
morals are concerned only about cases which  are objectively doubtful; 
hence they abstract entirely  from the wide sphere of certain, 
established truths. Now,  the latter class is by far the larger in 
moral theology  also; were it not so, human reason would be in a sorry  
plight, and Divine providence would have bestowed little  care on the 
noblest of its visible creatures and on their  highest goods, even in 
the supernatural order, in which a  full measure of gifts and graces 
was showered upon those  ransomed in Christ. The certain and undoubted 
portion  includes all the fundamental questions of Christian  morals; 
it comprises those principles of the moral order  by which the 
relations of man to himself, to God, to his  neighbour, and to the 
various communities are regulated;  it embraces the doctrine of the 
last end of man and of  the supernatural means of attaining this end. 
There is  only a comparatively small number of objectively obscure  and 
doubtful laws or duties that appeal to Probabilism or  Antiprobabilism 
for a decision. However, as has been  said, since the middle of the 
seventeenth century, the  interest of moral theologians centered in the 
question  about Probabilism or Antiprobabilism. 
Just as far from the truth is the second opinion of the  adversaries of 
Probabilism, vix., that this system  induces people to evade the laws 
and hardens them into  callousness. On the contrary, to moot the 
question of  Probabilism at all, was the sign of a severely  
conscientious soul. He who proposes the question at all  knows and 
confesses by that very fact: first, that it is  not lawful to act with 
a doubtful conscience, that he who  performs an action without being 
firmly convinced of its  being allowed, commits sin in the sight of 
God; secondly,  that a law, above all the Divine law, obliges us to 
take  cognizance of it and that, therefore, whenever doubts  arise 
about the probable existence of an obligation we  must apply sufficient 
care in order to arrive at  certainty, so that a frivolous disregard of 
reasonable  doubts is in itself a sin against the submission due to  
God. In spite of all this, it may happen that all our  pains and 
inquiries do not lead us to certainty, that  solid reasons are found 
both for and against the  existence of an obligation: under these 
circumstances, a  conscientious man will naturally ask whether he must  
consider himself bound by the law or whether he can, by  further 
reflections -- reflex principles, as they are  called -- come to the 
plain conclusion that there is no  obligation either to do or to omit 
the act in question.  Were we obliged to consider ourselves bound in 
every  doubt, the result, obviously, would be an intolerable  severity. 
But since before performing an action the final  verdict of our 
conscience must be free from doubt, the  necessity of removing in one 
way or another such doubts  as may have arisen, is self-evident. 
At first there was a lack of clearness with regard to  Probabilism and 
the questions connected with it.  Conflicting definitions of opinion, 
probability, and  certitude, could not but cause confusion. When works 
on  moral theology and practical manuals began to multiply,  it was 
inevitable that some individuals should take the  word "probable" in 
too wide or in too lax a sense,  although there can be no doubt that in 
itself it means  "something acceptable to reason", in other words, 
since  reason can accept nothing unless it has the appearance of  
truth, "something based on reasons which generally lead  to the truth". 
Hence it is that opinions were actually  advanced and spread as 
practicable which were little in  accord with the demands of the 
Christian Faith, and which  brought down upon them the censure of the 
Holy See. We  refer particularly to the theses condemned by Alexander  
VII on 24 Sept., 1665, and on 18 March, 1666, and by  Innocent XI on 2 
March, 1679. It is not Probabilism that  must be made responsible for 
them, but the vagaries of a  few Probabilists. 
As a result of these condemnations, some theologians  thought 
themselves obliged to oppose the system itself  and to side with 
Probabiliorism. Previous to this turn of  affairs, the Jansenists had 
been the most pronounced  adversaries of Probabilism. But they, too, 
had received a  setback when Innocent X condemned (31 May, 1653) in the  
"Augustinus" of Jansenius, then recently deceased, the  proposition: 
"Just men, with the strength now at their  disposal, cannot keep 
certain commandments of God even if  they wish and endeavour to do so; 
besides, they are  without the help of grace which might make it 
possible  for them", was taken from the work and rejected as  heretical 
and blasphemous. Now Probabilism was least  reconcilable with this 
Jansenistic thesis, which could be  maintained the easier, the stricter 
the moral obligations  laid upon man's conscience were and the severer 
the  system proclaimed as solely justified was. Consequently,  the 
adherents of the Jansenistic doctrine endeavoured to  attack 
Probabilism, to throw suspicion on it as an  innovation, to represent 
it even as leading to sin. The  exaggerations of a few Probabilists who 
went too far in  their laxity, gave an opportunity to the Jansenists to  
attack the system, and soon a number of scholars, notably  among the 
Dominicans abandoned Probabilism, which they  had defended till then, 
attacked it and stood up for  Probabiliorism; some Jesuits also opposed 
Probabilism.  But by far, the majority of the Jesuit writers as well as  
a vast number of other orders and of the secular clergy,  adhered to 
Probabilism. An entire century was taken up  with this controversy, 
which probably has not its equal  in the history of Catholic theology. 
Fortunately, the works on either side of this controversy  were not 
popular writings. Nevertheless, exaggerated  theories caused a glaring 
inequality and much confusion  in the administration of the Sacrament 
of Penance and in  the guidance of souls. This seems to have been the 
case  particularly in France and Italy; Germany probably  suffered less 
from Rigorism. Hence it was a blessing of  Divine Providence that there 
arose a man in the middle of  the eighteenth century, who again 
insisted on a gentler  and milder practice, and who, owing to the 
eminent  sanctity which he combined with solid learning, and which  
raised him soon after his death to the honour of the  altar, received 
the ecclesiastical approbation of his  doctrine, thereby definitively 
establishing the milder  practice in moral theology. 
This man is Alphonsus Maria Liguori, who died in 1787 at  the age of 
91, was beatified in 1816, canonized in 1839,  and declared Doctor 
Ecclesić in 1871. In his youth  Liguori had been imbued with the 
stricter principles of  moral theology; but, as he himself confesses, 
the  experience which a missionary life extending over fifteen  years 
gave him, and careful study, brought him to a  realization of their 
falseness and evil consequences.  Chiefly for the younger members of 
the religious  congregation which owed its existence to his fervent  
zeal, he worked out a manual of moral theology, basing it  on the 
widely used "Medulla" of the Jesuit Hermann  Busenbaum, whose theses he 
subjected to a thorough  examination, confirmed by internal reasons and 
external  authority, illustrated by adverse opinions, and here and  
there modified. The work, entirely Probabilistic in its  principles, 
was first published in 1748. Received with  universal applause and 
lauded even by popes, it went  through its second edition in 1753; 
edition after edition  then followed, nearly every one showing the 
revising hand  of the author; the last, ninth, edition, published 
during  the lifetime of the saint, appeared in 1785. After his  
beatification and canonization his "Theologia moralis"  found an even 
wider circulation. Not only were various  editions arranged, but it 
almost seemed as though the  further growth of moral theology would be 
restricted to a  reiteration and to compendious revisions of the works 
of  St. Alphonsus. An excellent critical edition of the  “Theologia 
moralis Sti. Alphonsi" is that of Léonard  Gaudé, C.SS.R. (Rome, 1905), 
who has verified all the  quotations in the work and illustrated it 
with scholarly  annotations. 
No future work on practical moral theology can pass  without ample 
references to the writings of St.  Alphonsus. Hence it would be 
impossible to gain a clear  insight into the present state of moral 
theology and its  development without being more or less conversant 
with  the system of the saint, as narrated in the article  PROBABILISM. 
The controversy, which is still being waged  about Probabilism and 
Ćquiprobabilism, has no  significance unless the latter oversteps the 
limits set  to it by St. Alphonsus and merges into Probabiliorism.  
However, though the controversy has not yet been  abandoned 
theoretically, still in everyday practice it is  doubtful if there is 
any one who follows other rules in  deciding doubtful cases than those 
of Probabilism. This  ascendancy of the milder school in moral theology 
over  the more rigorous gained new impetus when Alphonsus was  
canonized and when the Church pointed out in particular  that Divine 
Providence had raised him up as a bulwark  against the errors of 
Jansenism, and that by his numerous  writings he had blazed a more 
reliable path which the  guides of souls might safely follow amid the 
conflicting  opinions either too lax or too strict. During his  
lifetime the saint was forced to enter several literary  disputes on 
account of his works on moral theology; his  chief adversaries were 
Concina and Patuzzi, both of the  Dominican Order, and champions of 
The last decades of the eighteenth century may well be  called a period 
of general decadence as far as the sacred  sciences, moral theology 
included, are concerned. The  frivolous spirit of the French 
Encyclopedists had  infected, as it were, the whole of Europe. The  
Revolution, which was its offspring, choked all  scientific life. A few 
words about the state of moral  theology during this period may 
suffice. Italy was torn  asunder by the dispute about Rigorism and a 
milder  practice; in France, Rigorism had received the full  rights of 
citizenship through the Jansenistic movement  and held its own till 
late in the nineteenth century;  Germany was swayed by a spirit of 
shallowness which  threatened to dislodge Christian morals by 
rationalistic  and natural principles. The "general seminaries" which  
Joseph II established in the Austrian states, engaged  professors who 
did not blush to advance heretical  doctrines and to exclude Christian 
self-restraint from  the catalogue of moral obligations. Other German  
institutions, too, offered their chairs of theology to  professors who 
had imbibed the ideas of "enlightenment",  neglected to insist on 
Catholic doctrines of faith and  putting aside the supernatural life, 
sought the end and  aim of education in a merely natural morality. But 
in the  second decade of the nineteenth century the French  Revolution 
had spent itself, quiet had again followed the  turmoil, the political 
restoration of Europe had been  begun. A restoration also of the 
ecclesiastical spirit  and learning was also inaugurated and the 
gradual rise of  moral theology became noticeable. Apart from the 
purely  ascetical side there are three divisions in which this  new 
life was plainly visible: catechism, popular  instruction, pastoral 
Though it is the purpose of catechetical teaching to  instruct the 
faithful in the entire range of Christian  religion, in the doctrines 
of faith no less than in those  of morals, yet the former may also be 
conceived and  discussed with respect to the duties and the way by 
which  man is destined to obtain his last end. Hence, the  catechetical 
treatment of religious questions may be  regarded as a portion of moral 
theology. During the  period of "enlightenment", this branch had been 
degraded  to a shallow moralizing along natural lines. But that it  
rose again in the course of the past century to a lucid  explanation of 
the sum-total of the Christian doctrine,  is attested by numerous 
excellent works, both catechisms  and extensive discussions. To these 
may be added the more  thorough manuals of Christian doctrine intended 
for  higher schools, in which the apologetical and moral  portions of 
religious instruction are treated  scientifically and adapted to the 
needs of the time.  There is nothing, however, which prevents us from 
placing  these writings in the second of the above-mentioned  classes, 
since their aim is the instruction of the  Christian people, though 
principally the educated laymen.  It is true these works belong 
exclusively, even less than  the catechetical, to moral theology, since 
their subject- matter embraces the whole of the Christian doctrine, yet  
the morally destructive tendencies of Atheism and the new  moral 
questions brought forward by the conditions of our  times, impressed 
upon writers the importance of moral  instruction in manuals of 
Catholic faith. The last  decades in particular prove that this side of 
theology  has been well taken care of. Various questions bearing on  
Christian morals were extensively treated in monographs,  as e. g., the 
social question, the significance of money,  the Church's doctrine on 
usury, the woman question, etc.  To quote single works or to enter on 
the different  subjects in detail would exceed the limits of this  
The third line along which we noted an advance was called  the 
pastoral, that is, instruction which has as its  special aim the 
education and aid of pastors and  confessors. That this instruction is 
necessarily, though  not exclusively, casuistic, was mentioned above. 
The  scarcity of priests, which was keenly felt in many  places, 
occasioned a lack of time necessary for an all- round scientific 
education of the candidates for the  priesthood. This circumstance 
explains why scientific  manuals of moral theology, for decades, were 
merely  casuistic compendia, containing indeed the gist of  scientific 
investigations, but lacking in scientific  argumentation. The 
correctness of ecclesiastical doctrine  had been insured and 
facilitated by the approbation with  which the Church distinguished the 
works of St.  Alphonsus. Hence, many of these compendia are nothing  
else than recapitulations of St. Alphonsus's "Theologia  moralis", or, 
if following a plan of their own, betray on  every page that their 
authors had it always ready at  hand. Two works may here find mention 
which enjoyed a  wider circulation than any other book on moral 
theology  and which are frequently used even today: the Scavini's  
"Theologia moralis universa", and the shorter "Compendium  theologić 
moralis" by Jean-Pierre Gury, together with the  numerous revisions 
which appeared in France, Germany,  Italy, Spain, and North America. 
We must not, however, deceive ourselves by concluding  that, owing to 
the ecclesiastical approbation of St.  Alphonsus and his moral 
writings, moral theology is now  settled forever and, so to speak, 
crystallized. Nor does  this approbation assure us that all individual 
questions  have been solved correctly, and therefore the discussion  of 
certain moral questions remains still open. The  Apostolic See itself, 
or rather the Sacred Penitentiary,  when asked, "Whether a professor of 
moral theology may  quietly follow and teach the opinions which St. 
Alphonsus  Liguori teaches in his Moral Theology", gave indeed an  
affirmative answer on 5 July, 1831; it added, however,  "but those must 
not be reprehended who defend other  opinions supported by the 
authority of reliable doctors".  He who would conclude the guarantee of 
absolute  correctness from the ecclesiastical approbation of the  
saint's works, would make the Church contradict herself.  St. Thomas of 
Aquin was at least as solemnly approved for  the whole field of 
theology as St. Alphonsus for moral  theology. Yet, e. g, on the 
subject of the efficacy of  grace, which enters deeply into morals, St. 
Thomas and  St. Alphonsus defend wholly contradictory opinions; both  
cannot be right, and so may be freely discussed. The same  may be said 
of other questions. In our own days, Antonio  Ballerini above all made 
a simple use of this freedom of  discussion, first in his annotations 
to Gury's  "Compendium", then in his "Opus theologicum morale",  which 
was recast and edited after his death by Dominic  Palmieri. It rendered 
an eminent service to casuistry;  for though we cannot approve of 
everything, yet the  authority of various opinions has been carefully 
sifted  and fully discussed. 
Lately, attempts have been made to develop moral theology  along other 
lines. The reformers assert that the  casuistical method has choked 
every other and that it  must give place to a more scientific, 
systematic  treatment. It is evident that a merely casuistical  
treatment does not come up to the demands of moral  theology, and as a 
matter of fact, during the last  decades, the speculative element was 
more and more  insisted on even in works chiefly casuistic. Whether the  
one or the other element should prevail, must be  determined according 
to the proximate aim which the work  intends to satisfy. If there is 
question of a purely  scientific explanation of moral theology which 
does not  intend to exceed the limits of speculation, then the  
casuistical element is without doubt speculative,  systematic 
discussion of the questions belonging to moral  theology; casuistry 
then serves only to illustrate the  theoretical explanations. But if 
there is question of a  manual which is intended for the practical 
needs of a  pastor and confessor and for their education, then the  
solid, scientific portion of general moral-theological  questions must 
be supplemented by an extensive casuistry.  Nay, when time and leisure 
are wanting to add ample  theoretical explanations to an extensive 
casuistical  drill, we should not criticize him who would under these  
circumstances insist on the latter at the expense of the  former; it is 
the more necessary in actual practice. 
SLATER, A Short History of Moral Theology (New York.  1909); 
BOUQUILLON, Theologia moralis fundamentalis, (3rd  ed., Bruges, 1903), 
Introductio; BUCCERONI, Commentar. de  natura theologiœ moralis (Rome, 
1910); SCHMITT, Zur  Gesch. des Probabilismus (1904); MAUSBACH, Die 
kathol.  Moral, ihre Methoden, Grundsätze und Aufgaben (2nd ed.  1902); 
MEYENBERG, Die kath. Moral als Angeklagte (2nd ed.  1902); KRAWUTZKI, 
Einleitung in das Studium der kath.  Moraltheologie (2nd. ed. 1898); 
GERIGK, Die  wissenschaftliche Moral und ihre Lehrweisc (1910). 
Transcribed by Douglas J. Potter

From the Catholic Encyclopedia 
Copyright © 1913 by the Encyclopedia Press, Inc. 

Electronic version copyright © 1996 by New Advent, Inc.
All Rights Reserved


Provided courtesy of New Advent Supersite to:
Eternal Word Television Network
5817 Old Leeds Road
Irondale, AL 35210