How just are the judgments of God! In Rom. 2:16 St. Paul says: “God shall judge the secrets of men by Jesus Christ according to my gospel.” Notice carefully what this involves:
1⃣ He will judge “the secrets of men.” In human courts there are often miscarriages of justice because all the facts are not brought to light. But at the “Great White Throne” there will be a Judge with “eyes… as a flame of fire” (Rev. 19:12), before whom no secret can remain hidden. (See also Heb. 4:13).
2⃣ He will judge the secrets of men “by Jesus Christ.” Not the Father, but the Son will preside at the judgment of the unsaved. John 5:22 declares that “the Father judgeth no man, but hath committed all judgment unto the Son” and Verse 27 adds that the Father has given the Son this authority “because He is the Son of man.” This insures just judgment, for, men will be judged in that day by the One who loved them enough to become a man that He might understand and help men, and even die for their sins.
3⃣ He will judge the secrets of men by Jesus Christ “according to my gospel,” says Paul. How eminently fair and just this is. If He judged men according to the law of Moses no one ever would be saved, for all of us have broken the Law. Moreover the children of fallen Adam, because of their depraved nature, cannot consistently keep the Law. Thus they will not be judged on the basis of that which they were unable to live up to. This is why He will judge men according to the good news proclaimed by Paul, which is the great truth that salvation is denied to no one who takes God at His Word and approaches Him in His way. His way for today? “Believe on the Lord Jesus Christ and thou shalt be saved.”
“To him that worketh not, but believeth on Him that justifieth the ungodly, his faith is counted for righteousness” (Rom. 4:5). source