Let’s just admit it…no human has ever been able to keep the Old Testament Law perfectly. (that is except Jesus) Let’s also agree that the whole world is a prisoner of sin. So what these verses are showing is that the Law’s purpose was to essentially silence us, leaving us unable to defend ourselves against the charge of sin, while recognizing our guilt before God. So the Law’s objective was to lead us to acknowledge our sin and trust in Jesus Christ. Or as it tells us in Galatians, ” Know that a man is not justified by observing the Law but by faith in Jesus Christ.” And, “The righteous will live by faith. The Law is not based on faith…” Bottom line is…The real function of the Old Testament Law was to make us not only realize our own sinfulness, but then lead us towards repentance….which then leads us to faith and trust in Jesus.