John Wesley on Romans 2:16

In the day - That is, who show this in the day. Everything will then be shown to be what it really is. In that day will appear the law written in their hearts as it often does in the present life. When God shall judge the secrets of men - On secret circumstances depends the real quality of actions, frequently unknown to the actors themselves, Rom 2:29. Men generally form their judgments, even of themselves merely from what is apparent. According to my gospel - According to the tenor of that gospel which is committed to my care. Hence it appears that the gospel also is a law.