Let me quote the verses: For when Gentiles, who do not have the law, by nature do the things in the law, these, although not having the law, are a law to themselves, who show the work of the law written in their hearts, their conscience also bearing witness, and between themselves their thoughts accusing or else excusing them. I wish to deal with two main views of the passage. First things first, however.
Fascinating! There is no doubt that I find this fascinating. A Gentile (elect) unbelieving sinner is not delivered in conversion from the law, because he was never under the law to begin with. In John 1:8 it shows that all men are enlightened to some degree by God, and that all men have some sort of conscience and a knowledge of right and wrong, which is why, in the key text of Romans 2:14-15, Paul mentions this).
And then, Judaizers who tried (and still are trying) to bring believers back under the law; in the case of Gentiles who were never under the law to begin with, they can only bring them 'under the law of Moses', rather than 'back under the law of Moses', which would imply that they were once 'under the law' and are now delivered from it. Yes, this is fascinating.