Having just mentioned the disobedient in the days of Noah, Peter now wants to make a connection between what took place at the flood and what takes place today in Christian baptism.
Peter begins by describing the situation of the flood. The overwhelming majority of the world was wicked. In fact Peter states correctly that only 8 souls were saved. The way they were saved is shocking. We would expect Peter to say they were saved by the Ark. In our children stories and movies the Ark is the instrument that saves Noah and his family. Now it is true the Ark saved them from destruction of the Flood, but Peter states that it wasn’t the Ark that saved Noah, but rather water.
How did the water save Noah? The water saved Noah because it provided separation between Noah and sin, in his case the sinful wicked world around him. Water destroyed that sinful world and therefore saved Noah from its wickedness.
In verse 21 Peter ties the water of Noah with the water of baptism. Just like Noah’s water saved him, Peter says “baptism now saves you.” It is one of the clearest statements in Scripture with regards to the purpose of Christian baptism.
Peter clarifies his statement with a parenthetical remark. Baptism is not simply ritual washing. Ritual washing was a part of the 1st Century Jewish experience. Migvahs, which were baptistries, were common place throughout Palestine. In fact, many priests had them built in their homes. The purpose of Migvahs were to allow someone to dip before entering into service to God. It cleaned the body from ritual impurity. Peter states that this is not the purpose of Christian baptism.
Christian baptism is not the removal of impurities from the body, but rather the appeal of a good conscience toward God. The phrase “good conscience” was used already in 1 Peter 3:16. In that case a good conscience was maintained when Christians conduct themselves in God honoring ways. The initial achieving of this conscience happens at baptism. Appeal for a good conscience could be equated with “calling on the name of the Lord” in Acts. The idea is that once a person recognizes their sinfulness and need for salvation, they then put their trust in God for that salvation. This is culminated when a person is baptized.
Peter ends by stating how baptism saves. Peter is clear of the fact that baptism procures salvation, but it is not simply the act of being immersed in water that provides this status. Rather Peter states that baptism saves because of the Resurrection of Jesus. Those who teach falsely that baptism is a meritorious work that earns salvation have separated baptism from Jesus work on the cross. And those who teach that baptism is not needed for salvation make the same mistake. Baptism saves because of its connection with the death of Jesus.
Peter proclaims clearly that baptism saves us. It saves us like the waters of Noah’s day saved him. It saves us by separating us from sin. This salvation is made available because of Jesus Death and Resurrection. Those who are baptized are putting their faith in Jesus as they enter the water believing that God is working on them with the result being their salvation.