Baptism is a New Testament doctrine. It was started by John the Baptism. Baptism means immersion or to immerse. Water Baptism is the acceptable mode of baptism. John 3:1-6; Acts 8:38-39.
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Water Baptism is not what you do because others are doing it. It has a meaning and a significant. The Lord commanded in the great commission that those who believed the gospel should be baptized. The Apostles preached that peopl should repent and be baptized. Matthew 28:19; Acts 2:38. Jesus Christ was also baptized by immersion.
Baptism doesn't mean forgiveness of sin and regeneration. It is an outward expressing of an inward grace. It is an open declaration of ones repentance. When one is baptized by immersion one is baptized unto the death of Christ. The person immersed in the water is buried with Christ while in the water.when he is raised out of the water, he is raised up into a newness of life in Christ as Christ was resurrected to glory. This means he is dead to sin and alive unto righteousness. This gives us the hope of being like Him on the resurrection day. Romans 6:3-5.
Baptism is meant for those who have accepted Jesus Christ as Lord and saviour. It follows confession of faith. It is not for ordinary church goers. Acts 16:30-34.