EWTN Catholic Q&A
infallible Pope
Question from jackie on 10-22-2007:

I understand that the Pope is infallible when he speaks from the chair of Peter, I am not sure I even have that part right. Could you explain this and when the last time a Pope spoke infallibly and what it was he said. Thank you

Answer by Fr. Robert J. Levis on 10-23-2007:

Jackie, Vatican Council 1 defined papal infallibility. When the Pope speaks infallibly, ie. when discharging the office of pastor and teacher of all Christians, by virtue of his supreme apostolic authority, he defines a doctrine regarding faith or morals to be held by the universal Church, by the divine assistance promised to him in Blessed Peter,the Pope possesses that infallibility with which the divine Redeemer willed his church to possess. Pope Pius 12 in 1950 solemnly defined the dogma of the Assumption of the Blessed Virgin Mary into Heaven. But the Pope also enjoys the ordinary episcopal infallibility of the Church whenever he teaches the Faith. Fr. Bob Levis