symbolizes the baptism: Peter might mean that, just as the water lifted the boat that saved Noah and his family, baptism brings believers into salvation. Or he may mean that, just as Noah and his family passed through water to reach safety, Christians pass through the waters of baptism as part of their salvation. A third possibility is that, just as the water in Noah’s day judged sin, the water of baptism shows the washing away of sin for Christians.
Peter does not mean that water baptism saves a person regardless of that person's inner attitude. He explains that baptism saves only as a response to God from a clean conscience (or an appeal to God for a clean conscience). In this way, he makes clear that only people who exercise faith toward God will benefit from baptism.