Galatians 3:19-22

Why the Law then? It was added because of transgressions, having been ordained through angels by the agency of a mediator, until the seed would come to whom the promise had been made. Now a mediator is not for one party only; whereas God is only one. Is the Law then contrary to the promises of God? May it never be! For if a law had been given which was able to impart life, then righteousness would indeed have been based on law. But the Scripture has shut up everyone under sin, so that the promise by faith in Jesus Christ might be given to those who believe.