2:38 Repent and be baptized. Repentance (turning to God in sorrow for sin) and baptism were important parts of the message of John the Baptist (Matt. 3:1; Mark 1:4) and of Jesus (Matt. 4:17; 11:20; Luke 13:3, 5), and were central in the church’s preaching and teaching (Matt. 28:18, 19). See “Baptism” at Rom. 6:3.
in the name of Jesus Christ. A summary of Matt. 28:18, 19 (baptism in the name of the Father, Son, and Holy Spirit), with only Jesus mentioned here, since Peter’s sermon had to do with Jesus and His ministry.
for the forgiveness of your sins. Baptism is a sign and seal of spiritual cleansing the Spirit effects through the forgiveness of sins (Titus 3:5).
the gift of the Holy Spirit. The gift of the indwelling Person of the Holy Spirit, as well as the gift of forgiveness (Eph. 1:7), and of empowering for ministry. It is significant that Peter does not speak here of receiving the gift of tongues. The gifts of forgiveness and the indwelling Holy Spirit are essential for producing the fruit of the Spirit in the lives of believers (Gal. 5:22, 23) and for exercising the gifts the Spirit chooses to give at different times to different believers (1 Cor. 12:4–11).