There are many popular approaches that people take toward God’s holy law as laid down in scripture.
For some God's law is like a poison. Run away fast, and for that matter, run far too. As you go warn everyone within earshot to steer clear of the law for it is fatal to any enjoyment of God whatsoever.
For others God’s law is treated like old clothes from the 1970’s. As plaid bell-bottom slacks were eventually dismissed, the law is dismissed as an embarrassment, something we’re glad to be done with. In this view the law is not heinous it is just out of touch. We have no use for the law because the Lord of New Testament is more easy-going than the Lord of the Old.
For still others the law is treated like a report card. It offers a standard that allows us to check whether or not we are making the grade with God. If our relatively exemplary behavior surpasses the relatively poor behavior of others, then we are pleasing to heaven. In this view the law is used to tell me I'm okay with God and other people are not - assuming a generous grading curve of course.
But these three views of the law are misconceptions.
What Law Does
Let’s recall what God’s law does. The law tells us we are transgressors. "The law was added so that the trespass might increase" (Romans 5:20). The law is that Word from God that reveals in its standards that lawlessness reigns in our hearts. It exposes how far we fall short of the glory of God: "Indeed I would not have known what sin was except through the law" (Rom. 7:7).
As Jesus taught in the sermon on the mount, the law's command, “Do not kill,” exposes as murderers all who have hated. “Do not steal,” exposes as thieves all who have coveted. "Do not commit adultery" exposes as adulterers all who have lusted after another person. The law exposes. It exposes all of us as having a nature that is contrary to the holy character of God. As fallen creatures we can not attain his standard. The law is not satisfied with mere approximations, it demands perfect, personal and perpetual obedience from the inside out. Thus it convicts all, condemns all and holds all men over for judgment. "We were held prisoners by the law, locked up until faith should be revealed" (Galatians 3:23).
The law, however, does prepare sinners. It prepares us to hear the gospel: "So the law was put in charge to lead us to Christ that we might be justified by faith" (Gal. 3:24).
What the Law Does Not Do
The law has a significant preparatory role in God’s plan of redemption, but it also has significant limitations. The law does not make anyone acceptable to God. A mirror shows a man he needs to shave, but the mirror is no razor. It does not provide what it reveals. So too the law. The law may awaken a sinner, but it does not convert him. It is a bill in the mail, not a check. It reveals debt, it does not settle it. “For we maintain that a man is justified by faith apart from observing the law” (Rom. 3:28). This is true for all the redeemed of the old covenant era and of the new. The law has never granted salvation to any man. "Know that a man is not justified by observing the law, but by faith in Jesus Christ" (Gal. 2:16).
So the law is not gospel. It is not good news for sinners. When we read the law in Sunday morning worship, we must not expect to be acquitted. We should, rather, expect to be exposed, to be found guilty.
Now these limitations of the law may lead us to think it is malicious. But it is not. "What shall we say, then? Is the law sin? Certainly not!" (Rom. 7:7). "So then,the law is holy, and the commandment is holy, righteous and good." (Rom. 7:12). We must never equate God’s law with legalism. Legalism derives from sinful man not holy God. Legalism is using your moral performance - over an hour or a lifetime - to assure yourself of some positive standing with God. But man’s standing with God has always been founded upon, and is only founded upon, God’s mercy alone in Christ alone. "But I trust in your unfailing love; my heart rejoices in your salvation.” (Psalm 13:5). So the damnable disease of legalism is not to be charged against the law. The law is not sin. Rather, legalism is to be charged against our fallen human heart. Fallen man distorts the law as surely as he distorts grace.
What Grace Does
So what does grace do? Grace makes promises to us right in the face of all our failings before the law. "The law was added so that the trespass might increase. But where sin increased, grace increased all the more" (Rom. 5:20). Every place God's word of law exposes sin, God's word of grace promises forgiveness and acceptance. At every point the law binds us, grace unbinds us. Law locks us up for judgment. Grace unlocks us, freeing us to live. Grace is the merciful work of God in Christ crucified to forever set free condemned sinners from the just terrors the law.
By dying with Christ, we have died to the law, that is we can no longer be condemned by it. Christ has met all its demands upon us. This good news of grace, in Christ Jesus, is the message that converts the sinner. "We love because he first loved us" (1 John 4:19). All who welcome this message of grace by believing it and calling out to Christ to whom it belongs receive the Holy Spirit and become lovers of God, determined followers of Christ (Gal. 3:5).
What Grace Does Not Do
Grace frees us from the condemnation of the law but grace does not free us from holiness. Grace does not release us from moral responsibility. Grace is not permissive. "What then? Shall we sin because we are not under law but under grace? By no means!" (Romans 6:1-2). Those who believe God’s message of grace in Christ do not use it as a license to live wickedly. On the contrary, those who have come to know God's love for sinners have now begun to love God. A strong ethical direction and affection for God has been embedded in their faith by God's own Spirit. "Those who obey his commands live in him, and he in them. And this is how we know that he lives in us: We know it by the Spirit he gave us" (1 Jn. 3:24).
No, grace is not permissive. It is unitive. By the Spirit the believer is united to Christ in his death and resurrection. He has taken your life up into his own and so you have overcome sin and death and now a sincere interest in God's righteous ways is necessarily coming forth in you.
The holy interests that had always been the eternal Son's by nature are now yours by grace.