Baptism is a physical symbol of a spiritual reality
Scripture says that the first step to take after believing the gospel is to be baptized. Baptism is a physical symbol of a spiritual reality: as you go down into the water you are acting out your old self’s death to sin, and as you emerge you symbolize that you’ve been washed in Christ’s blood and now live a new life (Romans 6:3-10). Baptism is also a public testimony to your faith, so that the world around you knows that you have a new identity in Christ.
Baptism FAQ

