Expositor's Bible Commentary Commentary 1 Peter 3:21

"which also after a true likeness doth now save you, [even] baptism, not the putting away of the filth of the flesh, but the interrogation of a good conscience toward God, through the resurrection of Jesus Christ;" — 1 Peter 3:21 (ASV)

Although the parallel between the OT deliverance of Noah’s family and NT salvation through Christ is not precise in every detail, Peter says that the water of the Flood-judgment portrays the water of baptism. Baptism is the counterpart of what is represented in the Flood, even the “fulfillment” of the OT deliverance from judgment. How does baptism “save” (GK 5392)? Peter says it does not concern an external washing from filth but relates to the “conscience” (GK 5287). In the proclamation of the Gospel, salvation from sin and its punishment is announced through Jesus’ death and resurrection. The announcement of the penalty for sin stirs the conscience and the Spirit brings conviction (Acts 2:37–38; Acts 13:37–41).

“The pledge of a good conscience toward God” renders a difficult expression in Greek. The thought appears to be as follows: The conviction of sin by the Spirit in the human mind calls for a response of faith or commitment to Christ and his work. This is concretely and “contractually” done in the act of baptism. Saving faith is expressed in baptism (cf. Acts 2:38–39). Salvation comes to people because Christ has risen from the dead.