Acts 2: 36 - 41
36 Let all the house of Israel therefore know assuredly that God has made him both Lord and Christ, this Jesus whom you crucified."
37 Now when they heard this they were cut to the heart, and said to Peter and the rest of the apostles, "Brethren, what shall we do?"
38 And Peter said to them, "Repent, and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit.
39 For the promise is to you and to your children and to all that are far off, every one whom the Lord our God calls to him."
40 And he testified with many other words and exhorted them, saying, "Save yourselves from this crooked generation."
41 So those who received his word were baptized, and there were added that day about three thousand souls.

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