In our American culture it is customary to bury a deceased person in a cemetery shortly after they have passed.
After Jesus’ death on the cross, He was buried in a tomb until He rose again from the dead. Burial is what we do for people who have died. The application of water baptism is for those who have died in Christ to their old life of sin. “In Him you were also circumcised, in the putting off of the sinful nature, not with a circumcision done by the hands of men but with the circumcision done by Christ, having been buried with Him in baptism and raised with Him through your faith in the power of God, who raised Him from the dead.” Colossians 2:11, 12 (NIV)
In the Israelite faith, circumcision was a sign that the individual stood in covenant relation with God. Now, for the Christian, water baptism is a parallel sign of our covenant relationship with God. Water baptism is a symbol of a believers union with Christ in His death, burial, and resurrection. “Do you not know that as many of us as were baptized into Christ Jesus were baptized into His death?” Romans 6:3 “Therefore we were buried with Him through baptism into death, that just as Christ was raised from the dead by the glory of the Father, even so also we should walk in newness of life.” Romans 6:4 NKJ
How believers are baptized: The form of baptism - Biblical baptism was always by immersion. The Greek word “baptizo” means to dip or place under. Christ’s own baptism demonstrated this. (Matthew 3:13-17) Philip baptizing the eunuch “went down into the water, came up out of the water.” (Acts 8:38, 39)
The command to be baptized:
Matthew 28:19 - “teaching all nations, baptizing them…” Mark 16:16 - “He that believeth and is baptized…”
Acts 2:38 - “Repent and be baptized every one of you.” Acts 10:48 - “He commanded them to be baptized.”