Have you ever done the wrong thing and strategized in your mind about how you were going to spin your bad behavior to get into the least amount of trouble possible? Was your spin effective? Were you able to fool someone into giving you a pass for your bad behavior? Were you able to avoid getting into trouble? We might be able to trick someone into thinking better of us than we deserve, but it is impossible to fool God. According to Paul, God’s law is entirely effective at pointing out our sins. It silences all of our excuses and demonstrates that every person is guilty before God (Romans 3:19). Because of the universality of human guilt, no one can be justified in God’s sight by the deeds of the law (Romans 3:20, 28). The law cannot solve the sin problem; the best the law can do is point out the sin problem (Romans 3:20). Since we try to hide, deny, or excuse our sin, exposing sin is a necessary and essential function of God’s law that continues to this day.
Our justification by faith in Jesus apart from the deeds of the law helps to humble our pride and prevent boasting in moral and ethnic superiority (Romans 3:27, 28). By recognizing our moral failures and our inability to save ourselves by the deeds of the law, we are better able to have compassion for the faults of others.
Some are tempted to see a radical distinction between Paul’s understanding of the law and the Old Testament understanding of the law. This is a mistake. According to Paul, his own understanding of the law is consistent with the Old Testament (the Law and the Prophets) understanding of the law (Romans 3:21). Both Paul and the Law and the Prophets (the Old Testament) teach that we can’t save ourselves by our works and that salvation would come through Jesus, apart from our obedience to the law (Romans 3:21, 22). In fact, Paul’s understanding of salvation by faith establishes the truthfulness of God’s law (Romans 3:31). Throughout the book of Romans, Paul works hard to show that all of his teachings are consistent with the Old Testament teaching. He does this by citing Old Testament scriptures and narratives.
Another one of Paul’s reasons that salvation can’t be by the law is that it would limit the reach of salvation to the Jews alone, since they alone were given the law (Romans 3:28, 29). Since God is the God of the whole world, and everyone needs salvation from the universal problem of sin, the plan of salvation must be big enough to include everyone. Faith in Jesus is universally accessible to all people (Romans 3:22–26, 30).