Two passages are often conflated when thinking about the subjects of circumcision and baptism. Read these (and the greater contexts) first:
“In him also you were circumcised with a circumcision made without hands, by putting off the body of the flesh, by the circumcision of Christ, having been buried with him in baptism, in which you were also raised with him through faith in the powerful working of God, who raised him from the dead. And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses…”
“Is this blessing then only for the circumcised, or also for the uncircumcised? For we say that faith was counted to Abraham as righteousness. How then was it counted to him? Was it before or after he had been circumcised? It was not after, but before he was circumcised. He received the sign of circumcision as a seal of the righteousness that he had by faith while he was still uncircumcised. The purpose was to make him the father of all who believe without being circumcised, so that righteousness would be counted to them as well, and to make him the father of the circumcised who are not merely circumcised but who also walk in the footsteps of the faith that our father Abraham had before he was circumcised.”
The argument is made that since baptism is the New Testament version of circumcision (Col 2), and since Abraham was justified prior to circumcision (Rom 4), then this proves that one is saved prior to baptism, thus showing that baptism is not necessary (just like circumcision). Sounds pretty solid, right?
Not really. The problem here is that these two texts are speaking to two different contexts. A mistake is made when we try to take an analogy too far, forcing a one-to-one correlation on every aspect of it. Neither of these texts do that.
Look at Romans 4. The point being made has to do with the Jew and Gentile situation. Jews might take pride in the fact that they had the covenant of circumcision, but they were missing one major fact: Abraham was justified by faith before the command to be circumcised was even given. Because Abraham was “the father of us all,” the Jews could not bind circumcision on the Gentiles. We should note, though, that Abraham obeyed the command to be circumcised as soon as it was given. What if he had refused to do it at that point? Note also that nowhere in the text of Romans 4 is there any equation to baptism. That wasn’t the point being made.
Now look at Colossians 2. Here baptism and circumcision are explicitly compared in one particular, and one particular only: they both involve the “putting off” of something. Just as in circumcision there was a cutting off of the flesh, so in baptism there is a “putting off the body of the flesh.” The only comparison being made here is in the concept of cutting away something, which, again, was not the point Paul was making about Abraham in Romans 4.
In Colossians, Paul continues to say that baptism, which is a putting off the body of flesh (i.e., sin), entails being “buried with him in baptism, in which you were also raised with him through faith in the powerful working of God.” Notice that in baptism one is submitting to the working of God, rather than it being one’s own work. This is important because many will argue against baptism on the grounds it is a work, and since we are not saved by works, then it cannot be necessary. But that misses the point: submitting to baptism is trusting in the working of God; it is something done to you. Is it necessary for us to trust God’s work or not?
Paul also writes that “you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses…” The equation here is that one is dead in uncircumcision, then, through being buried with Christ in baptism and raised through faith in the powerful working of God, God makes this one alive by forgiveness. This aspect of baptism corresponds, not to Romans 4, but to Romans 6:1-5.
To take the narrow point about baptism correlating to one aspect of circumcision in Colossians 2, then squeezing that into what is said about circumcision in Romans 4, is to change the points being made. They aren’t the same.
Again, what if Abraham refused to be circumcised after the command was given? We know that would have been a problem because it would have shown a lack of faith (trust) on Abraham’s part. He did it right away, and that’s the kind of faith we are to imitate. When we know God wants something, we are not to wait.
When it comes to baptism, the command is already given. It’s not like the situation with Abraham and circumcision wherein the command was yet to be given. We already have it. What, then, if we refuse or put it off because it is not convenient for us? This will earn us nothing, for it is always by God’s grace that salvation is given.
If you want to demonstrate faith (trust) in God’s working, how long will you wait to be baptized?