This verse takes up the main thread of the subject. “God will judge Jew and Gentile alike at the last day.” It cannot refer (as some would make it) to what immediately precedes, because there the Apostle is referring to the daily process that goes on whenever doubtful actions are submitted to the law of conscience, here he is speaking expressly of the final judgment held by God and not by man.
By Jesus Christ. — As the Son of God is the Mediator of salvation, so also is He the Mediator of judgment. The function of judgment is specially committed to Him. This is the consistent teaching of Scripture. (Comp. John 5:27, “the Father hath given Him authority to execute judgment also, because He is the Son of Man”; Acts 17:31, “He hath appointed a day in the which He will judge the world... by that Man whom He hath ordained”; 1 Corinthians 4:5; 2 Corinthians 5:10, et. al.)
According to my gospel. — How is this to be taken? To what is it that the gospel, as preached by St. Paul, testifies? It may be either to the simple fact that God will judge the secrets of men, or to the particular law or standard by which He will judge them. Probably, on the whole, the former is the preferable explanation. “In the day when, as I teach, God will judge the secrets of men by Jesus Christ.”