What does the ceremony of baptism really mean? What does your baptism mean to you? Paul explains in Colossians 2:11–12.
Christ has brought you into a covenant relationship with himself. The Old Testament sign sealed a special relationship with God. Circumcision was more than a sign of national identity. It was a seal of the covenant God had made with Abraham and his descendants, Genesis 17:7ff. It symbolized the removal of defilement, Jeremiah 4:4; 6:10. Too often Israel trusted in the outward sign, but that alone, without trust in God and a life of covenant obedience was worse than worthless.
A sign points to something beyond itself. Christ has done what the sign pictured. This is the powerful Christ of Colossians 2:9, 10. In him the (sinful) flesh is put off — not a surgical operation, but a cleansing from sin. He breaks the power of sin and sets you apart to be God’s holy, pure people.
In baptism you have been buried and raised with Christ. You are united with Christ in his death and resurrection. Christ died and was buried, and you died with him. You are dead to the guilt of your sin, and to its enslaving power over you. Christ was raised, and you have been raised with him. You are a new creature in Christ. You are united to your covenant God.
Baptism is more than a sign. This union is sealed in your baptism. God graciously gives you a sign and seal of this union. Baptism is into the name of the Trinity. (Paul is not making a point about the mode of baptism in this passage.) Baptism parallels the sign of the old covenant. Note the close connection within verses 11 and 12. This sign is broader (it includes females), and more gracious (no surgical operation is required). While the sign does not save, don’t neglect it. If God commanded it, it is important.
“The Old Testament sign and rite of initiation into the covenant community, circumcision, signified the same spiritual blessings as the New Covenant sign and rite of baptism. The great difference is that in the New Covenant the outward sign has been changed form a bloody sacrament to an unbloody sacrament.” (p. 21)
“So just, like circumcision, baptism was never intended to be an outward sign only, but was to point us to even greater realities: that God gives new life; that God justifies; that God sames! These ceremonial signs do not save in themselves but teach us to cling to the grace of God as found in Jesus Christ.” (p. 22)
“Our circumcision in baptism is to be identified with Christ’s circumcision on the cross as he bore the curse of our covenant breaking…. So when were we circumcised by Christ? In [Colossians 2] verse 12 the apostle gives the explanation, basically saying, ‘You were circumcised when you were baptized.’… It is important to recognize here that the benefits of being identified with Christ’s death and resurrection that are signified in baptism do no benefit us without faith. Paul speaks of our ‘faith in the powerful working of God” (Col. 2:12).” (p. 24)
Daniel R. Hyde, Jesus Loves the Little Children
Because you have been baptized, trust the power of God in Christ Jesus. The union you have with Christ is a union by faith. This was also true of the sign in the Old Testament, Romans 4:11. Covenant child, your baptism calls you to respond to God in faith. For each of you, your baptism, and witnessing the administration of the sign to others, is a call to continue to trust your Savior.
You have been purified. You have been cleansed, not by the physical operation of circumcision, but by the saving work of Christ, which God has sealed to you in your baptism.