Because of the Fall of Adam, all men descending from him by natural generation are under God’s wrath and curse. And so every person deserves damnation, not only because of the guilt of Adam imputed upon him, but also because of his corrupt nature and rebellion against God. Now, man is created in the image of God, and so every man has a natural conscience (Rom 2:14–15). But the mind is darkened by the Fall and the conscience dulled so that unless God reveals to us in clear concerning the misery to come, most of us will simply drift along and fail to take heed to the danger that awaits our souls. This is why God gives us His laws, especially the Moral Law which is summarised in the Ten Commandments. These commands show us the standard of holiness required by God, and so at the same time shows how far short we fall: “by the law is the knowledge of sin” (Rom 3:20). We may say that the Law of God is like a portrait displaying the holiness of God and, at the same time, a mirror reflecting our shortfall.
Man ought to walk according to the Law. But this is impossible because of indwelling sin and because the Law demands more than mere outward conformity. This fact is especially highlighted through the Lord’s summary of the Ten Commandments in Mathew 22:37–40; for here, we are taught that to keep the Law is synonymous to loving God and loving man perfectly. In other words, the Law must be kept in love. The believer must delight in God with His whole being and so obeys Him out of love. At the same time, the basis of our obedience in regards to the laws that pertain to our relationship with our neighbour must be founded not only upon our love for God, but upon our love for our neighbour.
But there is a problem. Under the illumination of the Holy Spirit, we know that it is impossible for us to keep the demands of God because we are naturally inclined to hate God and our neighbours. The Apostle Paul, relating his conversion experience, tells us: “I was alive without the law once: but when the commandment came, sin revived, and I died” (Rom 7:9). Before his conversion, Paul was very sure he had kept the laws perfectly, but once the Holy Spirit regenerated his soul, he realised that he had not kept the Law at all, and was in fact unable to keep the Law perfectly, according to the demands of God.
It is under this circumstance that the Law shuts us up to Christ. Thus Paul exclaims: “O wretched man that I am! who shall deliver me from the body of this death? I thank God through Jesus Christ our Lord” (Rom 7:24–25a). The Law, under the illumination of the Spirit, shows our inability to save ourselves, so that we have no recourse but to cast ourselves upon Christ; and “conclude that a man is justified by faith without the deeds of the law” (Rom 3:28). Rather, he is “justified freely by his grace through the redemption that is in Christ Jesus” (Rom 3:24).