Baptism is a washing with water (see 1 Peter 3:21; Hebrews 9:10; Titus 3:4–7). Typically one would either be immersed in a pool or have water poured over one's head or hands. The Jews regularly practised such washings for the purpose of ritual purification so that they could be part of the camp and meet with God at the temple (see Exodus 29:4; Exodus 30:19; Exodus 40:12, Exodus 40:30–31; Leviticus 8:6; Leviticus 11:32; Leviticus 14:8–9, Leviticus 14:51–52; Leviticus 15:5–8, Leviticus 15:10–13, Leviticus 15:16–18, Leviticus 15:21–22, Leviticus 15:27; Leviticus 16:4, Leviticus 16:24, Leviticus 16:26, Leviticus 16:28; Leviticus 17:15; Leviticus 22:6).1
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 will receive the gift of the Holy Spirit.