Romans 3:19-20, 27-28

Now, we realize that everything the law says is addressed to those who are under its authority. This is for two reasons: So that every excuse will be silenced, with no boasting of innocence. And so that the entire world will be held accountable to God’s standards. For by the merit of observing the law no one earns the status of being declared righteous before God, for it is the law that fully exposes and unmasks the reality of sin.

Where, then, is there room for boasting? Do our works bring God’s acceptance? Not at all! It was not our works of keeping the law but our faith in his finished work that makes us right with God. So our conclusion is this: God’s wonderful declaration that we are righteous in his eyes can only come when we put our faith in Christ, and not in keeping the law.