2:17 But if, in our endeavor to be justified in Christ, we ourselves were found to be sinners, is Christ then an agent of sin? Certainly not! 18 But if I build up again those things which I tore down, then I prove myself a transgressor.
Paul is saying here that, by endeavoring to be justified in Christ, all Jews by Nature now find themselves to be Sinners. Paul and Peter are now Sinners. Once they leave the protective covering of the Law, once they cross the dividing wall between Sinners and Jews by Nature, they themselves become Sinners. But, if by no longer following the Law by following Christ, and so are now said by all good Jews to be Sinners, was it Christ then who was an “agent of sin” by making them to be sinners, by destroying the wall dividing Jews by Nature and Sinners from the Gentiles? NO! But, once I’m over the wall, once I no longer trust the Law, I can no longer build it up again. If I do so, if I rebuild the Law dividing Sinners from Jews, then I am now permanently a Sinner, since I have broken the Law by leaving its protection.
In other words, Paul is telling Peter and other Jews, once you leave the protection of being a Jew by Nature in order to follow Christ, in the eyes of all good Jews, you are now a Sinner from the Gentiles, with no hope at all of salvation. You are a “sinner.” But only from their perspective. You are now in Christ. But you can’t go back. You can’t do both. If you try to rebuild the wall like Peter did again between Jews and Sinners and try to put yourself back on the side of Jews, you are a Sinner, since you have already transgressed the Law. You can’t just go back.
2:19 For I through the law died to the law, that I might live to God. 20. I have been crucified with Christ; it is no longer I who live, but Christ who lives in me; and the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me. 21 I do not nullify the grace of God; for if justification were through the law, then Christ died to no purpose.
A Jew who has not believed is now going to look at someone like Paul and say that Christ was an “agent of sin” for Paul, that Christ caused Paul to become a Sinner, outside the Law. Paul is therefore telling Peter and all other Jews: It is all or nothing. You can’t rebuild the wall of separation spoken about in Ephesians 2:14, since if you do, you will find yourself on the side of the Sinners from the Gentiles. You have to die to the Law, just as Christ died to the Law, since he became a curse by hanging on a tree, as Paul explains later in Galatians 3:13. Christ died to the Law by becoming cursed by the Law. The Law was its own undoing; by cursing, it blessed. Christ died to the law, and thereby found himself to be a “sinner among the gentiles.” But he therefore lived for his Father, “lived for God.” We too must go through the same process, dying to the Law with its restrictive claims to salvation.
Yet I cannot “die to the law,” since I cannot do what Jesus did, taking upon myself the curse of the law and hanging from a tree. The only way I can be on the other side of the Law and not be a Sinner is to be in Christ. That is the only way. Or else I am just a Sinner. I have to now live in a new place, and that is in Christ. I have to be crucified in his crucifixion, and allow him to live in me, or else I am just a Sinner. He is the only one who actually died and took the curse, so he must now live in me. Only thus can I also die. All I have left as a Jew outside the Law – now considered a “sinner from the Gentiles” by all law-abiding Jews – is faith in Christ. That is now my only hope for salvation.
By dying, Christ undid the law. Now, if justification is through the law, then Christ died in vain, since it can still bring salvation. But, says Paul to Peter, the law can no longer fulfill that function. As he says later in 3:24, the Law was our babysitter until Christ should come. Now, it has no function. You can’t go back to it after you have left it. You can’t go back to the babysitter when the parents come home. The Cross of Christ has replaced the Torah and all of its works. Yet only Christ can actually die to the Law by taking the curse upon himself. Therefore, for me to find salvation, he must live in me.
Nathan O'Halloran, SJ