QUESTION: What sin was repented of to obey the Acts 2:38 command?

ANSWER: The text of Acts 2.38 reads: “Peter replied, Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins. And you will receive the gift of the Holy Spirit.’” The call for repentance was a common call for the Jews to heed. The word “repent” meant to turn around form what you were doing and move back toward God. It meant to give up the way you though you could get to God and follow a different way. It was not a specific “sin” that Peter or Luke, the writer of Acts had in mind.