For we hold that one is justified by faith apart from works of the law. Or is God the God of Jews only? Is he not the God of Gentiles also? Yes, of Gentiles also, since God is one—who will justify the circumcised by faith and the uncircumcised through faith (Romans 3.28-30).

Medieval Roman Catholics and others have believed that there is one God. How does it help Paul’s argument, if it is an argument directly tied to moral works, to point out that God is one? What is theoretically problematic with the position that the one god will reward Jew and Gentile alike for their moral behavior? Yet Paul says that God is both God of the Jews and Gentiles as a counterargument against a position.

On the other hand, if “works of the law” are the things that mark out “those of the law” then it all make perfect sense. “For we hold that one is justified by faith apart from being a Jew,” or “For we hold that one is justified by faith apart from circumcision,” both make perfect sense.

And it also makes sense of the promise Paul keeps mentioning.

For the promise to Abraham and his offspring that he would be heir of the world did not come through the law but through the righteousness of faith. For if it is those of the law who are [exclusively] to be the heirs, faith is null and the promise is void. For the law brings wrath, but where there is no law there is no transgression. That is why it depends on faith, in order that the promise may rest on grace and be guaranteed to all his offspring—not only to the one of the law but also to the one who shares the faith of Abraham, who is the father of us all, as it is written, “I have made you the father of many nations” (Romans 4.13-17a; emphasis added).

Traditionally, in the name of a theory about what it means that the law brings wrath, people have read the entire argument as one of obedience as opposed to grace. But while Paul has much to say about the law, and makes a point about it here, his argument regarding the promise is not a theory of promised gifts versus earned wages, but rather the nature of what was promised (“the world [kosmos],” “many nations”) versus the Law which was tied to one nation, Israel. Those who say that Israel’s status is permanant are restricting the grace of God to a few and denying the promise to all who believe.