Paul takes the objection to its logical end. If sin brings God glory, why not say, "Let us do evil, that good may come"? Stated that plainly, the idea shows itself to be wrong. Paul also had a personal reason. Some were already slandering him by claiming he taught this. Barnes says this was "probably" a twisting of Paul's teaching that "where sin abounded, grace did much more abound" (Romans 5:20). Paul "expressly disavows" it and teaches, Barnes says, "a great fundamental law, that evil is not to be done that good may come."

Paul answers in the same breath: "whose damnation is just" (Romans 3:8). He does not argue the point further here; the idea deserves condemnation, not debate. He returns to it later, asking, "Shall we continue in sin, that grace may abound? God forbid" (Romans 6:1-2), and again in Romans 6:15.

The KJV phrase "slanderously reported" translates one Greek verb, blasphemoumetha, "we are blasphemed." Barnes notes that this is "the legitimate and proper use of the word blaspheme, to speak of one in a reproachful and calumnious manner." In other words, Paul's enemies were spreading lies about what he preached.

The KJV word "damnation" translates krima, judgment or condemnation, which the ESV renders "condemnation." The Greek reads literally "whose judgment is just."

The gospel of grace was misunderstood this way even in Paul's day. Because God justifies sinners freely (Romans 3:24), some conclude that sin no longer matters. Paul treats that conclusion as a lie about his message, not a fair reading of it.

Matthew Henry adds a searching thought: "Let us do evil that good may come is oftener in the heart than in the mouth of sinners, so justifying themselves in their wicked ways." Few people say it out loud, but many live as though it were true. Grace does not make sin safe; it frees people from sin, as Paul shows in Romans 6:1-7.