11 For there is no respect of persons with God.
12 For as many as have sinned without law shall also perish without law: and as many as have sinned in the law shall be judged by the law;
13 (For not the hearers of the law are just before God, but the doers of the law shall be justified.
14 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:
15 Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another
16 In the day when God shall judge the secrets of men by Jesus Christ according to my gospel.
When the gentiles do what is right, and proclaim, This is right, they demonstrate the knowledge of right and wrong, authenticating the accuracy of God's judgement when . . .
as many as have sinned without law shall also perish without law: and as many as have sinned in the law shall be judged by the law;
Having your conscience tell you that you don't sin is not the same thing as not sinning. In saying that you judge some things right, and some things wrong, this makes no statement about your acceptibility to God. But what it does do is to say that you know better, so even though you were not given the Jewish Law, yet still you know better, and you will be judged accordingly.
Much love!