Seven Purposes of the Law in Deuteronomy

In my reading through the Deuteronomy this month, I was struck by the clarity that God and Moses offered the people as to why they were given this Law. The people are told at multiple times that God has given them this law for specific purposes. Each of God’s commands is given with distinct purposes. As believers, understanding these purposes is crucial because they inform our view of God’s will and help us understand the Law’s continued role by understanding God’s intent.

Expectation of Obedience

From creation to revelation, God’s commands come with the expectation of obedience. The Bible begins with God’s command in Genesis 1:3, “Let there be light,” and creation obeys his Word. It closes with the expectation that the saints “keep the commandments of God” (Revelation 14:12) and that those who hear the words of prophecy will keep them (Revelations 22:7). When God speaks to a people, he expects them to do what he says.

This expectation is consistent throughout Deuteronomy. God says, “Now what I am commanding you today is not too difficult for you or beyond your reach … No, the word is very near you; it is in your mouth and in your heart so you may obey it” (Deuteronomy 30:11–14). Moses emphasizes that the people are to “obey” (6:24) and “do them” (4:14). Even when God knows they will fail (as he tells them in 31:16–18) the expectation of obedience remains (11:26–28). This unchanging standard reveals his will and frames the law’s purposes.

Seven Purposes of the Law

1. To Show True Life and Blessing

Deuteronomy 4:1, “Now, Israel, listen to the statutes and the judgments which I am teaching you to perform, so that you will live and go in and take possession of the land which the Lord, the God of your fathers, is giving you.”

Deuteronomy 6:1–2, “Now this is the commandment, the statutes, and the judgments which the Lord your God has commanded me to teach you, so that you may do them in the land where you are going over to take possession of it, so that you, your son, and your grandson will fear the Lord your God, to keep all His statutes and His commandments which I command you, all the days of your life, and that your days may be prolonged.

Obeying the law promised life. The contrast, disobedience, brought death (Deuteronomy 27:26). God says that he intends the Law as a means to sustain them. God teaches his people his Law in order to inform them how to live before him. Jesus reiterates this principle after saying he didn’t come to abolish the law, but to fulfill it by saying “whoever keeps and teaches [the Law], he shall be called great in the kingdom of heaven” (Matthew 5:19). James encourages the believer to not only study the Law but to be active in obedience because “this person will be blessed in what he does” (James 1:25).

God gave the Law to show his people what true life and blessing looked like.

2. To Reveal God to the Nations

Deuteronomy 4:5–8, “See, I have taught you statutes and judgments just as the Lord my God commanded me … So keep and do them, for that is your wisdom and your understanding in the sight of the peoples who will hear all these statutes and say, ‘Surely this great nation is a wise and understanding people.’ For what great nation is there that has a god so near to it as is the Lord our God whenever we call on Him? Or what great nation is there that has statutes and judgments as righteous as this whole Law which I am setting before you today?’”

Deuteronomy 28:1, “Now it shall be, if you diligently obey the Lord your God, being careful to do all His commandments which I am commanding you today, that the Lord your God will put you high above all the nations of the earth.”

The Law shows God’s people as set apart from the world. It displays God’s wisdom and justice to surrounding nations. Their obedience testifies to his character. The Law serves a missional purpose that glorifies God among the nations. Jesus told his disciples, “You are the light of the world. A city set on a hill cannot be hidden; Your light must shine before people in such a way that they may see your good works, and glorify your Father who is in heaven” (Matthew 5:14–16). Peter also says this is true of NT believers, “Beloved, I urge you … keep your behavior excellent among the Gentiles, so that in the thing in which they slander you as evildoers, they may because of your good deeds, as they observe them, glorify God on the day of visitation” (1 Peter 2:11–12).

God gave the law to reveal himself to the nations, through the fruitfulness of his saints as a witness to his glory.

3. To Mark God’s Covenant People

Deuteronomy 7:12, “it shall come about, because you listen to these judgments and keep and do them, that the Lord your God will keep His covenant with you and His faithfulness which He swore to your forefathers.”

Deuteronomy 29:10,12–13, “You stand today, all of you, before the Lord your God … so that you may enter into the covenant with the Lord your God, and into His oath which the Lord your God is making with you today, in order that He may establish you today as His people, and that He may be your God…

Deuteronomy 26:18, “And the Lord has today declared you to be His people, His personal possession, just as He promised you, and that you are to keep all His commandments.”

The law defines the terms of the covenant; who is in and who is out. God gave his Law in order to identify his people as his own. The Law sets them apart through obedience. Jesus said the same “If anyone loves Me, he will follow My word; and My Father will love him, and We will come to him and make Our dwelling with him” (John 14:23–24) And he further clarifies that this obedience will be taught by the Holy Spirit: “the Holy Spirit whom the Father will send in My name, He will teach you all things, and remind you of all that I said to you” (John 14:26). This is in fulfillment of his prophecy spoken through Jeremiah “I will put My law within them and write it on their heart; and I will be their God, and they shall be My people” (Jeremiah 31:33). The apostle John also says “Whoever keeps His commandments remains in God, and God in him. And by this we know that He remains in us: by the Spirit He has given us” (1 John 3:24).

God gave the Law to mark his covenant people; his people are revealed by his Spirit in their obedience.

4. To Define Righteousness and Holiness

Deuteronomy 6:25, “And it will be righteousness for us if we are careful to follow all this commandment before the Lord our God, just as He commanded us.”

The Law shows what a right standing before God looks like. It was given to a people for them to see the perfect and holy reflection of God’s moral character. It shows what is true and right and good. The Law aligns perfectly with God’s character and establishes a standard of righteousness that cannot be matched. Paul in his letter to the Roman church, affirms that God’s Law is of righteous design, “the Law is holy, and the commandment is holy and righteous and good” (Romans 7:12). Jesus said he intended to “fulfill all righteousness” (Matthew 5:15) and “to fulfill” the Law (Matthew 5:17) and this is the perfect righteousness that is the basis of our own salvation (1 Corinthians 1:30; Romans 5:19; 2 Corinthians 5:21). Paul argues that “love is the fulfillment of the Law” (Romans 13:10; see also Galatians 5:14) and this matches Jesus’ summary of the Law (Mark 12:29–31; Matthew 22:37–40). From this expression Jesus also commands, “If you love Me, you will keep My commandments” (John 14:15).

God gave the Law to define righteousness and holiness, guiding his people to mirror his nature.

5. To Guide and Guard the Heart in Truth

Deuteronomy 11:16–21, “Beware that your hearts are not easily deceived, and that you do not turn away and serve other gods, and worship them. Otherwise, the anger of the Lord will be kindled against you …. “You shall therefore take these words of mine to heart and to soul; and you shall tie them as a sign on your hand, and they shall be as frontlets on your forehead. You shall also teach them to your sons …. And you shall write them on the doorposts of your house … so that your days and the days of your sons may be increased on the land which the Lord swore to your fathers to give them, as long as the heavens are above the earth.”

God warned that turning away from the Law would leave the heart vulnerable. The Law was to act as a guide and a guard for the heart. It was intended to protect against the deception of idolatry and untruth. God expects believers to internalize his words and guard our actions (hand) and minds (forehead), and identity (doorposts) against false belief. The truth of God’s law is eternal. Jesus said the truth of the Law would not pass away (Matthew 5:18). Paul argued that being “justified by faith,” we do not “nullify the Law,” instead “we establish the Law” – we prove that it is true (Romans 3:28, 31). Jesus showed us to resist temptation by the Word when he responded to the devil: “‘Man shall not live on bread alone, but on every word that comes out of the mouth of God’” (Matthew 4:4). Jesus also prayed for believers to be sanctified in the truth of the Word (John 17:17) and said this would be accomplished by the work of the Holy Spirit guiding us in this truth (John 16:13). And Peter exhorts the believers to live out the Word of God in a “sincere love” since our “obedience to the truth” has purified our souls.

The Law guards the heart against false belief and guided by the Spirit gives instruction in true knowledge.

6. To Promote Their Well-Being

Deuteronomy 10:13, “… keep the Lord’s commandments and His statutes which I am commanding you today for your good.”

Deuteronomy 6:24, “So the Lord commanded us to follow all these statutes, to fear the Lord our God for our own good always and for our survival, as it is today.”

The Law is a gift. It is a benefit, not a curse. It is designed to enhance flourishing and prevent languid ineffectiveness. God’s gift of ordinances instructs his people in spiritual and physical welfare. God’s commands reflect his care, aiming for their good in every area of life. Paul assumes believers know this truth when he says, “we know that the Law is good, if one uses it lawfully” (1 Timothy 1:8; cf. Romans 7:12). Jesus compared a man who “hears these words” and “does them” to a “wise man who built his house on the rock,” showing how the man survived the floods because of its foundation (Matthew 7:24–25). He even said that “those who hear the word of God and follow it” are to be blessed more than his own mother who carried him in her womb (Luke 11:27–28)! In Jesus' last message to his disciples before his crucifixion he showed how obedience results in the fullness of joy: “If you keep my commandments, you will abide in my love … These things I have spoken to you so that … your joy may be made full” (John 15:10–11). Paul says the believer, “according to the Spirit,” now walks in the fulfilled Law (Romans 8:4) with his mind set on life and peace (8:6).

God gave the Law to promote the well-being of his people, a generous gift for their flourishing through walking in the Spirit.

7. To Cultivate Fear and Reverence

Deuteronomy 13:4, “You shall follow the Lord your God and fear Him; and you shall keep His commandments, listen to His voice, serve Him, and cling to Him.”

Deuteronomy 10:12–13, “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 and love Him, and to serve the Lord your God with all your heart and with all your soul, and to keep the Lord’s commandments and His statutes which I am commanding you today for your good?”

Deuteronomy 14:23, “You shall eat in the presence of the Lord your God, at the place where He chooses to establish His name, the tithe of your grain, your new wine, your oil, and the firstborn of your herd and your flock, so that you may learn to fear the Lord your God always.”

The Law trains God’s people to fear him; to stand in awe of him; to revere his holiness and honor him as worthy of obedience. Each command and precept reveals his holiness and his perfect demands. Obedience is a posture of humility. It yields the lesser to the greater. True fear deepens our worship and our faith. Paul says our “fear and trembling” before God is necessary for the working out of our own salvation (Philippians 2:12); Jesus said that we should “fear the One who, after He has killed someone, has the power to throw that person into hell” (Luke 12:5). While the disobedient will not enter the eternal rest, as believers “we must fear … for we who have believed enter that rest” (Hebrews 4:1). The same author says that serving God “with reverence and awe” stems from a grateful recognition of his salvation, “for our God is a consuming fire” (Hebrews 12:28–29). Paul says that believers cannot join with those who act against the Law and that “the fear of God” leads to perfect holiness (2 Corinthians 6:14–7:1). In the New Covenant, the Holy Spirit produces this holy fear as his presence is revealed (Acts 5:5, Acts 9:31, Acts 19:17).

God gave the Law to cultivate fear and reverence, turning his people away from lawlessness and toward holiness.

Conclusion

These seven purposes – showing true life and blessing, revealing God to the nations, marking His covenant people, defining righteousness and holiness, guiding and guarding the heart in truth, promoting well-being, and cultivating fear and reverence – define God's intent in Deuteronomy. God gave the Law with the expectation of obedience. He requires perfect obedience. This was fulfilled through Jesus Christ in his life work and perfect sacrifice. As believers who have turned from sin and trusted in his death and resurrection, we are filled with his Spirit that fulfills this Law in us. His Spirit writes the Law on our heart, teaches us it's truths, empowers us to obey them, sanctifies us by their standard, and produces a holy fear and reverence for God in light of them.

“… if by the Spirit you are putting to death the deeds of the body, you will live. For all who are being led by the Spirit of God, these are sons and daughters of God.” (Romans 8:13–14)