Baptism isn’t required for salvation, but is the first step of faith for believers. The baptismal waters don’t save anyone. It’s Jesus that does that. Baptism is a picture of the work that Jesus has done in a person’s heart.
Baptism illustrates Christ’s death, burial, and resurrection. (1 Corinthians 15:3-4) It shows our new life as a follower of Christ. (2 Corinthians 5:17) Baptism doesn’t make you a believer… it shows that you already believe. Baptism doesn’t save you; Jesus does! Baptism is like a wedding ring, signifying a relationships rather than forming that relationship.
We follow Jesus’ example in baptism. He was baptized (Mark 1:9), and commanded us to be baptized (Matthew 28:19-20).