Charles Spurgeon Commentary Romans 3:27-31

"Where then is the glorying? It is excluded. By what manner of law? of works? Nay: but by a law of faith. We reckon therefore that a man is justified by faith apart from the works of the law. Or is God [the God] of Jews only? is he not [the God] of Gentiles also? Yea, of Gentiles also: if so be that God is one, and he shall justify the circumcision by faith, and the uncircumcision through faith. Do we then make the law of none effect through faith? God forbid: nay, we establish the law." — Romans 3:27-31 (ASV)

It is excluded. By what law? Of works? Nay: but by the law of faith. Therefore we conclude that a man is justified by faith without the deeds of the law. Is he the God of the Jews only? Is he not also of the Gentiles? Yes, of the Gentiles, also: seeing it is one God, which shall justify the circumcision by faith, and uncircumcision through faith. Do we then make void the law through faith? God forbid: yea, we establish the law.

Whether Jews or Gentiles, there was no salvation for them by the works of the law; the only way in which the circumcised or the uncircumcised could be justified was by faith. This principle does not make void God's law; on the contrary, it establishes it, and sets it on the only right and solid foundation. The gospel of the grace of God is the best vindication of his law.