“For the wrath of God is revealed from heaven against all ungodliness and wickedness of those who by their wickedness suppress the truth” (1:18) It looks like Paul is still developing this theme, focusing on groups that think themselves exempt, e.g., the Jews.
Commentators wonder who these Gentiles who “do instinctively what the law requires” are: a strictly hypothetical group, righteous non-Christians, Christians? None of the proposed identifications are without problems.
Some 2,000 years out from Paul’s writing, today’s text sounds like it could as easily be written about Christians as a group. Paul: “For it is not the hearers of the law who are righteous in God’s sight, but the doers of the law who will be justified.” And already Paul’s contemporary James finds it necessary to remind his Christian readers “For if any are hearers of the word and not doers, they are like those who look at themselves in a mirror; for they look at themselves and, on going away, immediately forget what they were like” (Jas. 1:23-24). What do I do with that?