Galatians 3:17-21

17And this I say, that the covenant, that was confirmed before of God in Christ, the law, which was four hundred and thirty years after, cannot disannul, that it should make the promise of none effect.

18For if the inheritance be of the law, it is no more of promise: but God gave it to Abraham by promise.

19Wherefore then serveth the law? It was added because of transgressions, till the seed should come to whom the promise was made; and it was ordained by angels in the hand of a mediator.

20Now a mediator is not a mediator of one, but God is one.

21Is the law then against the promises of God? God forbid: for if there had been a law given which could have given life, verily righteousness should have been by the law.