What does Romans 3:7 mean?

Paul returns again to the question raised in verse 5, somewhat re-phrasing it, using a more specific example. This challenge strikes at Paul's argument about God's judgment on human sinfulness. The basic claim is this: If telling a lie further displays God's truthfulness, leading to His glory, why should He condemn me for that lie? Paul has previously said that our sin does indeed result in proving God's righteous sinlessness. So if our sin brings glory to Him, in a sense, should He really condemn us for it?

Paul states in the following verse that some people were accusing him of teaching exactly this: that human sin leads to God's glory, so we might as well do more of it. Paul refutes the very idea of this in two directions. First, God's righteousness means, by definition, that He cannot be unrighteous. He is the standard of goodness and truth, so His judgment of our sin is by definition completely fair and justified. We deserve it.

Second, as Paul will write in the following verses, human sinfulness is inevitable. We do not sin, in any way, with an intent to bring glory to God. We sin because we are sinners. Later, Paul will more directly refute that salvation is a license to sin (Romans 6:1). For now, particularly in the next verse, he will brush aside this criticism as rank slander (Romans 3:8).