"Therefore let all the house of Israel know assuredly, that God hath made the same Jesus, whom ye crucified, both Lord and Christ. When they heard this they were pricked in their hearts and said unto Peter and the rest of the apostles, Men and brethren, what shall we do? Then Peter said unto them, Repent and be baptized every one of you, in the name of Jesus Christ for the remission of your sins, and ye shall receive the gift of the Holy Ghost." - Acts 2:37,38
Recommended reading:
The Bible
Is the Bible Infallible?
