The Jews had an important advantage over every other people on earth. They had the very words of God. That should have made them the most faithful people! But they were unfaithful. Did this mean that God was unfaithful? Not at all! Even if every human being on earth were a liar, God would be faithful. That is one of his immutable characteristics. In fact, Israel's failure brought out God's faithfulness more clearly-God's punishment of sin exhibits his faithfulness to his righteousness. Nor can we say that God shouldn't judge our sin because our sin is showing God's righteousness. Paul likens it to saying, "Let us do evil that good may result." That is absurd!
Verses 9-18 are verses from various Psalms and Isaiah. They are strong evidences that no one is righteous. Not any one of us! Paul's conclusion of these verses is that no one can be made righteous by observing the law. There is no hope that we can make ourselves righteous with our own behavior. We can't adhere to God's standard of perfection. That's what the law requires. Instead, we have faith in God, who sent Jesus Christ our Lord, that whoever believes in him shall have eternal life, as God has promised.
Application: Father, no one is righteous, not even one. We should be condemned as sinners. But you are faithful, promising redemption through Jesus Christ. Save us through him!
One Word: We are accountable to faithful God