But since he had just explained that the unbelief of the Jews had manifested the truth of God to the glory of God, such thoughts could arise in a Jew trained in scholastic argument by the Greeks: if our unrighteousness magnifies God’s righteousness, why should wrath be brought upon us? That would be unjust. However absurd such a thought is, it could diminish fear of God’s judgment, calm the unbeliever who had begun to be troubled, and thereby cut off his path to faith. Foreseeing this, the Apostle speaks as though to the Jew: you do not believe, and you think that this is nothing. No, God’s dread judgments will fall upon your head. Do not let that evasion of falsehood deceive you, as though, since your unrighteousness reveals God’s righteousness, God will not bring upon you the punishment you deserve for your unbelief. Can one really reason that, since our unrighteousness establishes God’s righteousness, God would be unrighteous in bringing wrath, and therefore will not bring it? Do not reason this way. You will not escape God’s punishment, and God, in bringing wrath upon you, will not be unrighteous in the least.
This thought directly serves the Apostle’s aim: to shake the Jew’s self-confidence and, by awakening a sense of danger for himself, dispose him to repentance and faith. “I speak as a man,” the Apostle added, in order to show that his own tongue would not have turned to say such a thing, nor would it ever have entered his mind. Yet men, as I have heard, sometimes reason this way. In Greek the thought is this: if our unrighteousness reveals God’s righteousness in glory, will God not be unjust in bringing wrath? This, he says, I speak as a man. “Notice the Apostle’s reverence. Having said, ‘Is God unjust who brings wrath?’ he added, ‘I speak as a man.’ Anyone reasoning according to human understanding would say this” (Chrysostom). “He says, I do not pronounce this on my own behalf, but present the reasonings of others” (blessed Theodoret).
Or “I speak as a man” is better joined with what follows: “Let it not be,” in the sense that even if one reasons humanly, this can in no way be said. With God there may be grounds that we cannot even conceive. “So, he says, I answer in justification of God according to human reason, that is, as much as a sound-minded man can answer. For the works of God have certain grounds incomprehensible to us. They surpass human reason and have no need of our defense” (blessed Theophylact). “For the righteous judgment of God incomparably surpasses what is just according to our reasoning” (Chrysostom).
The speculation that God would be unjust if He punished those whose unrighteousness reveals His righteousness is not truth. It is the clever evasion of a crafty, advocate-like mind. Unrighteousness here means the same as unbelief earlier. The Jews did not believe, after they had been led toward belief throughout their entire history. Therefore they are unrighteous. Yet God, despite this, fulfilled His promise. The Lord came and accomplished the salvation of all. This justified the truth of the promises and manifested in a strong light the boundless goodness of God. This is what the words mean: it establishes God’s righteousness.
“Establishes,” from the Greek, means presents or manifests. It makes God’s righteousness shine brightly above our unrighteousness. Yet while illuminating it, it does not unite with it, nor form one thing with it. The Apostle sets forth here precisely this lack of union. He gives to God’s righteousness what belongs to it, and to our unrighteousness what belongs to it. Does our unrighteousness reveal God’s righteousness by its own nature or by our intention? No. Our unrighteousness is essentially unrighteousness. When we gave ourselves over to wrong, we did not even think that God’s righteousness would be manifested through it. It would have been strange to think so. We only followed our own reasoning and did our own will. If God’s righteousness has now shone over such a manner of our action, it can in no way be attributed to that action as its fruit. Consequently, it cannot give that action a right to reward, or at least shelter it from righteous wrath and punishment. God, in His boundless wisdom and goodness, makes our unrighteousness reveal His righteousness. To Him be glory; to us, wrath. For this in no way changes our unrighteousness into righteousness.