“For when the Gentiles, which have not the law, do by nature the things contained in the law, these, having not the law, are a law unto themselves:”
King James Version (KJV)
2:14 For when the gentiles - That is, any of them. St. Paul, having refuted the perverse judgment of the Jews concerning the heathens, proceeds to show the just judgment of God against them. He now speaks directly of the heathens, in order to convince the heathens. Yet the concession he makes to these serves more strongly to convince the Jews. Do by nature - That is, without an outward rule; though this also, strictly speaking, is by preventing grace. The things contained in the law - The ten commandments being only the substance of the law of nature. These, not having the written law, are a law unto themselves - That is, what the law is to the Jews, they are, by the grace of God, to themselves; namely, a rule of life.
Ro 2:14 When Gentiles, which have not the law. No revelation, such as the Jews had. They had a law of nature (Ro 1:18,32). Do by nature the things contained in the law. Paul has shown how the general principle that "God will render to every man according to his works" (Pr 24:12 Mt 16:27 2Ti 4:14) applies to the Jews; they will be judged by law, and only law-doers will be justified. He now shows that the same principle applies to the Gentiles. They have no revealed and written law like the Jews, but in case Gentiles, without it, should keep the things contained in the law, the moral principles of the law of Moses, they are a law to themselves. Their consciences and moral sense are a law. The apostle does not say that this was the rule among the Gentiles, but applies the principle to the very rare instances of Gentiles of pure character.