Romans 3:29–31, “29 Or is God the God of Jews only? Is he not the God of Gentiles also? Yes, of Gentiles also, 30 since God is one—who will justify the circumcised by faith and the uncircumcised through faith. 31 Do we then overthrow the law by this faith? By no means! On the contrary, we uphold the law.”
If justification is by faith alone apart from the works of the law, boasting is excluded because there is no possible way we can give ourselves any credit for our right standing before God. Not even the good we do in cooperation with the Lord’s grace gives us reason to boast, for this good follows justification and is not the basis of it (Rom. 3:27–28). Yet as the Apostle Paul teaches in today’s passage, justification by faith alone does not overthrow or do away with the law of God but upholds it. Justification by faith alone reveals the law’s true purpose and provides the way forward in fulfilling it.
Verses 29–30 offer a supporting argument based on Jewish monotheism as to why justification must be by faith alone apart from the works of the law. Paul contends that there must be only one way of justification because there is only one God. This in itself was not objectionable to the Apostle’s Jewish contemporaries, for they likewise believed that Yahweh was not only the covenant Lord of Israel but also the one true God, regardless of whether the Gentiles recognized it (Ex. 20:3; Isa. 44:6). Jews who denied Christ, however, disagreed with Paul on what the one way of justification entailed. For them, it was submission to the Mosaic law, including circumcision. Paul says that this cannot be. After all, how could Gentiles be justified by the law of Moses if they have never been under the law of Moses? Yes, they are under the moral law of God, but they are not bound by the specifically Jewish ceremonies and regulations given to Israel (Rom. 2:12–16). Jews and Gentiles have different ethnic and religious backgrounds, but there is only one God, and He has only one way of justification—one that is by faith and not by the very law that separates Jew and Gentile.
Finally, justification by faith alone does not overthrow the law; rather, it upholds the law’s purpose in justification. John Calvin comments, “The moral law is in reality confirmed and established through faith in Christ, inasmuch as it was given for this end—to lead man to Christ by showing him his iniquity; and without this it cannot be fulfilled, and in vain will it require what ought to be done; nor can it do anything but irritate lust more and more, and thus finally increase man’s condemnation; but where there is a coming to Christ, there is first found in him the perfect righteousness of the law, which becomes ours by imputation.” Only by denying that our doing of the law can justify us will we uphold the God-ordained purpose for the law in our justification, namely, to drive us to Christ.
Calvin also writes that after justification “there is sanctification, by which our hearts are prepared to keep the law; it is indeed imperfectly done, but there is an aiming at the work.” Sanctification follows justification, so justification upholds the law also in that once we are justified and receive the Holy Spirit, only then can we begin to do what the law requires. The justified do what God commands, albeit not perfectly and never in a way that merits righteousness before the Lord.