from Adrian Rogers' devotional book What Every Christian Ought to Know Day by Day

We have been joined with Him in the likeness of His death. Romans 6:5

This passage says that baptism is a picture of the death, burial, and resurrection of Jesus Christ—and of our death, burial, and resurrection with Him. Remember, baptism pictures and symbolizes the saving gospel of Christ. That’s the reason why we must adhere to the method, because if you change the method, you destroy the picture.

Baptism is a living, repeating portrait of the gospel. It pictures our identification with the Lord. “For in that He died, He died to sin once for all; but in that He lives, He lives to God” (Rom. 6:10). This is baptism’s testimony.