On Pentecost Sunday, Peter presented the gospel and showed how the Old Testament prophesied the death of the Messiah and His subsequent resurrection. He said to the Jews:

Repent, and each of you be baptized in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit (Acts 2:38).

This verse is confusing for many because it appears that Peter commanded repentance and baptism to receive forgiveness of sins and the gift of the Spirit. However, Peter preached the message of salvation without mentioning baptism several times, so clearly baptism is not required for salvation.

After healing the lame man, Peter said to the gathering crowd:

Therefore repent and return, so that your sins may be wiped away (Acts 3:19).

Peter didn’t say anything about baptism at that time. He told the people to repent, to change their minds about their sin, and turn to God through faith in Jesus Christ, and their sins would be wiped away.

After telling the Jewish Council that they had hung the Messiah on a cross, Peter said:

He is the one whom God exalted to His right hand as a Prince and a Savior, to grant repentance to Israel, and forgiveness of sins (Acts 5:31).

Peter presented forgiveness of sins in the context of repentance. The theme, “repentance for forgiveness of sins” runs throughout the Book of Acts. Repentance was to be publicly declared through water baptism.

We find Peter preaching to the Gentiles at the house of Cornelius:

Of Him [Christ] all the prophets bear witness that through His name everyone who believes in Him receives forgiveness of sins (Acts 10:43).

After the Gentiles believed, and the Holy Spirit was poured out on them, Peter said:

Surely no one can refuse the water for these to be baptized who have received the Holy Spirit just as we did, can he? (v. 47).

In Acts 2:38, Peter was instructing the Jews to be baptized as a testimony of their faith in Jesus Christ. Baptism proclaimed a person’s identification with Christ—no secret disciples were allowed.

Repentance alone brings forgiveness and the indwelling of the Holy Spirit. The water baptism that follows is a testimony to that repentance. Water baptism is not necessary for salvation, but it is an important part of a believer’s testimony. Peter called on the Jews to believe in Christ for forgiveness of sin and to testify to that faith through water baptism.