19 Why then the law? It was added because of transgressions, until the offspring should come to whom the promise had been made, and it was put in place through angels by an intermediary. 20 Now an intermediary implies more than one, but God is one.
21 Is the law then contrary to the promises of God? Certainly not! For if a law had been given that could give life, then righteousness would indeed be by the law. 22 But the Scripture imprisoned everything under sin, so that the promise by faith in Jesus Christ might be given to those who believe.
23 Now before faith came, we were held captive under the law, imprisoned until the coming faith would be revealed. 24 So then, the law was our guardian until Christ came, in order that we might be justified by faith.
Having distinguished the various uses of the idea of law, perhaps we may be able to come to understand more clearly what Paul means when he uses it in this epistle, and what he does not mean.
We think, then, first of all, of law as expressive of the covenant relationship between God and man: 'I the Lord thy God, which have brought thee out of the land of Egypt, out of the house of bondage; thou shalt have no other gods before Me'. The law is therefore the expression of life within the covenant (not a method of entering into the covenant). God's will is to have fellowship with us. Since He is God, that will is expressed as a sovereign claim upon us. But since He is love, He desires that His sovereignty should be freely accepted by us. He wants to awaken a responsive love in us. Thus, the law, as God's explicit claim upon man, is to be understood in terms of the covenant established between man and God. When it is not thus understood, it degenerates into a righteousness of works. This is the distortion that Paul is battling against in Galatians.