Romans 2:16

in the day when God shall judge the secrets of men, according to my gospel, by Jesus Christ. [This verse relates to the thought interrupted by the parenthesis; i. e., the thought of Romans 2:13. Not hearers, but doers, shall be justified in the judgment-day, that day when God shall judge the secrets of men's lives and judge them, as my gospel further reveals, through Jesus Christ as judge. The Jewish Scriptures revealed a judgment-day, and the thought was not unfamiliar to the Gentiles; but it remained for Paul's gospel to reveal the new truth that Jesus was to be the Judge. Paul started with the thought that, in judging another, a sinner condemned himself (Romans 2:3). Having discussed that thought and shown that it is applicable to the Jew, because God's judgments rest on moral and not on national or ceremonial ground, the apostle here resumes it once more, in connection with Romans 2:13; that he may show that if the law of Moses did not shield from condemnation, neither would circumcision.]