He has been quoting a mosaic of Old Testament passages from the Psalms and Isaiah. He regards these as part of' the law,' which term, therefore, in his view, here includes the whole previous revelation, considered as making known God's will as to man's conduct. Every word of God, whether promise, or doctrine, or specific command, has in it some element bearing on conduct. God reveals nothing only in order that we may know, but all that, knowing, we may do and be what is pleasing in His sight. All His words are law.
But Paul sets forth another view of its purpose here; namely, to drive home to men's consciences the conviction of sin. That is not the only purpose, for God reveals duty primarily in order that men may do it, and His law is meant to be obeyed. But, failing obedience, this second purpose comes into action, and His law is a swift witness against sin. The more clearly we know our duty, the more poignant will be our consciousness of failure. The light which shines to show the path of right, shines to show our deviations from it. And that conviction of sin, which it was the very purpose of all the previous Revelation to produce, is a merciful gift; for, as the Apostle implies, it is the prerequisite to the faith which saves.
As a matter of fact, there was a far profounder and more inward conviction of sin among the Jews than in any heathen nation. Contrast the wailings of many a psalm with the tone in Greek or Roman literature. No doubt there is a law written on men's hearts which evokes a lower measure of the same consciousness of sin. There are prayers among the Assyrian and Babylonian tablets which might almost stand beside the Fifty-first Psalm; but, on the whole, the deep sense of sin was the product of the revealed law. The best use of our consciousness of what we ought to be, is when it rouses conscience to feel the discordance with it of what we are, and so drives us to Christ. Law, whether in the Old Testament, or as written in our hearts by their very make, is the slave whose task is to bring us to Christ, who will give us power to keep God's commandments.
Another purpose of the law is stated in Romans 3:21, as being to bear witness, in conjunction with the prophets, to a future more perfect revelation of God's righteousness. Much of the law was symbolic and prophetic. The ideal it set forth could not always remain unfulfilled. The whole attitude of that system was one of forward-looking expectancy. There is much danger lest, in modern investigations as to the authorship, date, and genesis of the Old Testament revelation, its central characteristic should be lost sight of; namely, its pointing onwards to a more perfect revelation which should supersede it.
