The Baptist Faith and Message (2000) defines baptism as:

“Christian baptism is the immersion of a believer in water in the name of the Father, the Son, and the Holy Spirit. It is an act of obedience symbolizing the believer’s faith in a crucified, buried, and risen Saviour, the believer’s death to sin, the burial of the old life, and the resurrection to walk in newness of life in Christ Jesus. It is a testimony to his faith in the final resurrection of the dead. Being a church ordinance, it is prerequisite to the privileges of church membership and to the Lord’s Supper.”

1. Outward sign of an inward faith. Baptism is, in essence, an outside sign of an inward faith. When one surrenders to Jesus, the old self dies and the new life in Christ takes over. Thus, immersion. Not only des the word ‘baptism’ mean to ‘immerse’ or ‘dip,’ this serves as a picture of dying and resurrection.  That’s what the sign signifies–a washing away of our sin, a dying to self, and being raised in Christ.
2. You are witnessing to others about Jesus. When you take the step of being baptized in front of others, specifically your church, you are testifying that Jesus is enough for you, no matter what others may say. Sure, you will be wet, you may slip on a stair going in, your hair will be messed up, etc., etc.  But this is all a part of telling others, “I do not care how I look, I do not care the cost, I will testify of my Lord and King, and count all things as loss.”
3. It is the first step of discipleship.  No, you do not need to be baptized to be saved (that’s for another blog post), but if you have pledged your allegiance to King Jesus, then doing the first and basic step He asks of you is a launching into a lifestyle of discipleship, of sitting at His feet and doing what He calls you to do out of love for Him.  If you refuse to follow in baptism, why? Why disobey the first thing He told you to do? Are you then really a disciple if you refuse to do this first step in living a life in Jesus?

Have you followed in believer’s baptism?  Tell me your story.  If you haven’t followed, why not?