Just as circumcision is circumcision of the heart, not the flesh, so baptism is spiritual baptism into the body of Christ through faith in Christ. Nothing wrong with either physical circumcision or physical baptism, but neither literally place you into the body of Christ. Water simply does not baptize you into the body of Christ. The Spirit of God does that, and at his choosing, before, during, or after water baptism. Since we don't emphasize water baptism as much as we used to (not a lot of creeks and lakes and nice weather readily available in most places to do that at the time a person comes to faith), most believers are saved long before they get water baptized. I was water baptized about two months after I received Christ by faith and was born again. It was important that I do that, but it had nothing to do with God saving me when I called on his name.