But now the righteousness of God apart from the law is revealed, being witnessed by the Law and the Prophets, even the righteousness of God, through faith in [of, King James Version] Jesus Christ, to all and on all who believe. For there is no difference.
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In the first part of the book of Romans, the apostle Paul showed that both gentiles (Greek ethnos, other nations) and Jews were guilty before God, having broken God’s holy laws and having earned the death penalty.
Since God’s laws are good and for our benefit, breaking them is self-destructive and causes us to fall far short of God’s glory. (See more about the fact that “All Have Sinned” in our commentary on Romans 3:23.)
So since all have sinned and no amount of law keeping can make up for even one sin in the past, the only way for sinners to be declared righteous is through Jesus Christ’s sacrifice. He paid the death penalty for anyone who believes in Jesus Christ and His sacrifice and who repents and commits to changing.
Paul says that this way to righteousness was witnessed by the Law and the Prophets. The Old Testament had prophecies about the Messiah who would be stricken for our transgressions (Isaiah 53:8). Also, Paul was setting the scene for the examples of Abraham and David that he uses in Romans 4.
This righteousness is a gift from God, and it could never be earned by law keeping. But it does not change the fact that God’s laws are good and that He commands us to obey them. Paul points out, “Shall we continue in sin that grace may abound? Certainly not! How shall we who have died to sin live any longer in it?” (Romans 6:1-2).