ISB ~ Acts 2 v38

Repent, and be baptized:The call for conversion is a call for Baptism, the sacrament that takes away sin and confers the Spirit (22:16; Jn 3:5; Tit 3:5). Here and elsewhere Peter insists that Baptism is the sacrament that brings us salvation (2:40; 1 Pet 3:21).

• The Council of Trent (1547) describes Baptism as the instrumental cause of our justification, i.e., the means used by Christ to cleanse us of guilt, fill us with the grace of divine life, and adopt us as children of God (Sess. 6, chap. 7; CCC 1226, 1262, 1427). in the name of Jesus: Not a complete baptismal formula like the trinitarian formula in Mt 28:19, but a thematic expression used in several ways in Acts. (1) Calling upon the name of Christ in Baptism (22:16) is linked with calling upon the name of the Lord for salvation in the earlier quotation from Joel (2:28-32). (2) The name distinguishes the Baptism of Jesus from the baptism of John (1:5; 19:2-5). (3) The name of Jesus is also invoked to work miracles and exorcisms (3:6; 4:30; 9:34; 16:18). See note on Acts 4:12.