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.
Paul's insistence that the law was not meant to be a means of justification leads necessarily to the question as to what is its point and function. This is in fact one of the biggest and most important issues in biblical doctrine, and we must now come to grips with it. We speak of law and gospel, in that order; but this is not in fact the biblical order. According to the Scriptures, gospel comes first, then law. This is seen in what is probably the greatest expression of the law - Exodus 20, which contains the Ten Commandments. It is significant that this great passage begins with the words, 'I am the Lord thy God which brought thee out...' - that is gospel; this is followed by 'Thou shalt...' - that is law. The law was therefore given after the redemption of Israel out of Egypt. Next, we need to see law in its proper setting. The relation of Old Testament to New is not so much that of law to grace as that of promise to fulfilment. The Old Testament was a covenant of promise, not of law. It was a promise of redemption that was given to Abraham (Genesis 12), and faith in the Old Testament is faith in the promise, not in the law. The whole of the Old Testament is, so to speak, a journey towards the fullness of the time when God sent forth His Son.
This, then, is the basic reality of the old economy - a covenant of promise, and to this the law was added, as Paul puts it here, because of transgressions, that is, in connection with the fact of sin. What this means we shall consider in the next Note.