1 John 1:5-7
“God is light and in him is no darkness at all. If we say we have fellowship with him while we walk in darkness, we lie and do not live according to the truth; but if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin.” (1 John 1:5-7)
The law of God is often likened in Scripture to light (e.g., Psalm 119:105). Like the streetlight, God’s law restrains evil (1 Timothy 1:9-10). God’s law does not control evil men, but it is a retarding influence to the forces of evil in the world. Some call this the political use of the law. By moral standards a society is held together. When moral standards loosen, a community or nation begins to come apart.
Like the light in the washroom, God’s law reveals man’s moral defilement (Romans 3:20; 7:7). By the law comes the knowledge of sin. If I do not believe I am dirty, I will not seek cleansing. If I do not think I am lost, I will not welcome a rescuer. But if I know that I am polluted and incapable of doing that which I wish to do, I will seek a savior and welcome him. This is the “custodian” work of the law that brings us to Christ (Galatians 3:24). The law in Paul’s sense here is not, strictly speaking, a teacher (“schoolmaster”). Rather, the law for the sinner is the school bus driver or even the truant officer to bring the lost to Christ. For the lawbreaker, the law makes sin very plain, “sinful beyond measure” (Romans 7:13). Thus the terrifying law condemns us and is designed to make people seek a way of escape. This is the evangelistic use of the law. If he does not flee to the Cross, the law becomes the basis for his judgment in the last day, and law will have failed in its evangelistic purpose (Romans 3:19).
For the Christian, the law has an entirely different function. Like the headlights on an automobile, the law for the Christian shows the way he must go if he is to reach the destination of being like Jesus.
The spiritual use of the law, or the instructional (didactic) use of the law is this standard which is the goal of our Christian life. Thus God’s purpose in giving the law is for our good, for our fulfillment, whether we are unsaved or saved.
And now, Israel, what does the LORD your God require of you, but to fear the LORD your God, to walk in all his ways, to love him, to serve the LORD your God with all your heart and with all your soul, and to keep the commandments and statutes of the LORD, which I command you this day for your good? (Deuteronomy 10:12-13)
Legalists forever want to turn it around and re-create people for the sake of the law, whereas Jesus insisted that the law (of the Sabbath) was made for man and not man for the law (Mark 2:27). “He puts that law into practice and he wins true happiness” (James 1:25, Phillips).
Man’s welfare, happiness, fulfillment is ever the purpose of a loving God. The more like him we become, the more we are fulfilled. This is the way of freedom, not restriction and bondage. James calls this the “law of liberty” (James 2:12). The tragedy of the lawless person is that he is forever diverted from the true and right trajectory. Righteousness is alignment with reality, and the one who is out of alignment with reality will finally destroy himself. But to be true and right, in alignment with ultimate reality, will make a person free, fulfill the purpose of his existence.
The person who abides by the rules of the game is the one who enjoys the game and the only one who is qualified to win. The owner who follows the instruction manual of the manufacturer is the one who finds satisfaction with the product. And so it is with traffic laws or criminal law — each is for our good. It is not simply that God rewards good behavior and punishes evil behavior, true as that may be. Sin brings its own punishment, righteousness its own reward: “The iniquities of the wicked ensnare him, and he is caught in the toils of his sin” (Proverbs 5:22).
This common theme of Scripture does not mean merely the obvious, that the drunkard may get hurt, will have a hangover, and often ruins his own life as well as others. It is even deeper than the truth that “the measure you give will be the measure you get” (Mark 4:24). The sin itself warps and ultimately destroys the person. Covetousness eats like cancer, taking away peace and joy, binding and demeaning the spirit—even if it does not lead to some other grosser behavior. In adultery a person sins against himself, depriving himself of the very things that make life worthwhile: love, security, belonging, fidelity, peace, integrity, the ecstasy of full oneness. Indeed, there is inherent punishment in sin (2 Peter 2:13).
On the other hand, “Great peace have those who love thy law; nothing can make them stumble” (Psalm 119:165). “And I shall walk at liberty, for I have sought thy precepts” (v. 45). The law is the birthright of all who are his. No wonder the longest chapter in the Bible is devoted to extolling the glorious wonders of the law of God (Psalm 119).
Note carefully that the purpose of God’s law is different from the purpose of regulations and laws in other religions. The law was never intended to make us righteous. There are passages in the Old Testament that sound as if the law had this purpose, and a few in the New Testament as well. (See Leviticus 18:5; Matthew 19:17) But Paul repeatedly emphasizes that no one—under the Old Covenant or under the New—has ever been or ever will be justified by obedience to the law: “For no human being will be justified in his sight by works of the law” (Romans 3:20; Gal. 2:16). Paul insists that this theme was taught in the Old Testament, from the days of Abraham (Romans 4:1-3) through David (vv. 4-8) to the age of the prophets (Galatians 3:11). Jesus himself clearly taught that none was good (Matthew 19:17), that even the best of us must be born from above (John 3:1-7) and are saved by grace through faith (vv. 14-16).
This truth of man’s depravity does not mean, of course, that every person is as wicked as possible, that no one ever does anything good. The uniform testimony of Scripture is that God’s image is marred, not totally effaced. God always recognizes and welcomes obedience and goodness. But all people sin and fall short of God’s glorious character (Rom. 3:23). No man is good enough to merit acceptance with God. No one is pure enough to be united with God.
Like a bridge halfway across the chasm, the works of a good person are all the more poignant in their utter inability to save. The law never was intended to make us righteous. The law simply shows us what we ought to be. For the lost sinner this is good news, for it leads him to the Savior. For the saved sinner this is good news, for it describes clearly what he is growing toward, what he longs to be in order to satisfy his Savior: likeness to Jesus Christ. With such a glorious purpose, our minds and hearts are moved to run to this wonderful gift of grace, the law. Ponder how you view the law. Is it to crimp your lifestyle or to provide the very things for which you yearn, love, security, belonging, fidelity, peace, integrity, and the ecstasy of full oneness? In which direction are you headed? Redirect if need be, towards all God created you to become.
 Numbers 32:23; Psalm 7:15; 9:15; 40:12; Proverbs 1:31; 11:1-31