Baptism pictures the disciple's identification with the person of Jesus and with his body - the church. It is a beautiful representation of what spiritually happens to you once you believe. When you are immersed in the water, it pictures death and the burial of your old life. When you are raised out of the water, it pictures being raised with Christ to walk in newness of life. It is a public testimony for others to see that you are a believer and follower of the Lord Jesus Christ!