What Were the Purposes of the Mosaic Law?
Question 10019
The law God gave to Israel through Moses at Mount Sinai has puzzled Christians for centuries. If we’re saved by grace through faith, why did God give the law? Was it a failed experiment? A temporary measure until something better came along? Or did it serve specific divine purposes that remain relevant for our understanding of God’s plan?
The New Testament, particularly in Paul’s letters, reveals multiple purposes for the Mosaic law. Understanding these purposes helps us appreciate both the law’s original function and why believers today are no longer under its jurisdiction.
To Reveal God’s Holiness and Standards
The law reveals the character of God—His holiness, righteousness, and moral perfection. When God declared, “You shall be holy, for I the LORD your God am holy” (Leviticus 19:2), He was establishing that His law reflects His very nature. The commands against murder, theft, adultery, and false witness tell us something about what God is like and what He values.
The Hebrew word for law, תּוֹרָה (torah), fundamentally means “instruction” or “teaching.” The law was God’s instruction manual for how a holy God wanted His people to live. It expressed divine standards that Israel was called to embody as God’s covenant people. As Psalm 19:7 declares: “The law of the LORD is perfect, reviving the soul.” The law is perfect because it perfectly reflects the perfect God who gave it.
To Reveal and Expose Sin
One of the law’s primary purposes was to expose sin for what it truly is. Paul states this clearly in Romans 3:20: “Through the law comes knowledge of sin.” And again in Romans 7:7: “If it had not been for the law, I would not have known sin. For I would not have known what it is to covet if the law had not said, ‘You shall not covet.'”
Think of it this way: without a standard, there can be no measurement of failure. The law provides the standard against which human behaviour is measured and found wanting. It’s like a ruler that reveals how short we fall. Or, as Paul puts it, the law is like a mirror—it shows us what we truly look like, spiritually speaking, and the picture isn’t pretty.
The law doesn’t merely identify sin; it also magnifies it. In Romans 5:20, Paul writes: “Now the law came in to increase the trespass.” This doesn’t mean the law made people more sinful in essence, but that it made the reality of sin more apparent. Where there was no law, sin was still present (Romans 5:13), but it was not “counted” or formally charged in the same way. The law shone a spotlight on human rebellion, making it unmistakably clear.
To Demonstrate Human Inability
Beyond revealing sin, the law demonstrated that human beings are utterly incapable of achieving righteousness through their own efforts. No one has ever kept the law perfectly—only Jesus. As Paul argues in Galatians 3:10: “For all who rely on works of the law are under a curse; for it is written, ‘Cursed be everyone who does not abide by all things written in the Book of the Law, and do them.'”
The law sets a perfect standard that no fallen human can meet. This was not a design flaw but a divine purpose. God intended for the law to shut every mouth and show that the whole world is accountable to Him (Romans 3:19). The law strips away all pretence of self-righteousness and forces us to acknowledge our need for a Saviour.
Romans 8:3 states that “the law, weakened by the flesh, could not do” what God accomplished through Jesus. The problem was never the law itself—”the law is holy, and the commandment is holy and righteous and good” (Romans 7:12). The problem was human flesh, the sinful nature that cannot submit to God’s law (Romans 8:7). The law was never intended to justify anyone but to demonstrate the impossibility of self-justification.
To Lead People to Jesus
Perhaps the most significant purpose of the law was to point people toward Jesus. Paul uses a striking image in Galatians 3:24: “So then, the law was our guardian until Christ came, in order that we might be justified by faith.” The Greek word translated “guardian” is παιδαγωγός (paidagōgos), which referred to a slave in a Greek household who supervised children, took them to school, and disciplined them until they came of age.
The paidagōgos wasn’t the teacher but the one who ensured the children got to the teacher. Similarly, the law wasn’t the ultimate goal but the means of bringing people to Jesus. It did this in several ways. The law exposed sin, creating the consciousness of guilt that drives people to seek forgiveness. It demonstrated the impossibility of self-salvation, shutting every escape route except faith in God’s grace. And it pointed typologically to Jesus through the sacrificial system—every lamb slain, every Day of Atonement, every sin offering whispered, “A greater sacrifice is coming.”
The author of Hebrews develops this extensively. The entire Levitical system—priests, sacrifices, tabernacle, festivals—were “a shadow of the good things to come” (Hebrews 10:1). They were never intended to provide ultimate forgiveness but to point forward to the one sacrifice that would accomplish what countless animal sacrifices never could.
To Set Israel Apart as God’s Covenant People
The law also served to distinguish Israel from the surrounding nations and mark them as God’s special covenant people. Many of the laws—dietary restrictions, clothing regulations, agricultural practices—had no obvious moral basis but served to create visible boundaries between Israel and the Gentile world.
In Deuteronomy 4:6-8, Moses told Israel: “Keep them and do them, for that will be your wisdom and your understanding in the sight of the peoples, who, when they hear all these statutes, will 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 the LORD our God is to us, whenever we call upon him? And what great nation is there, that has statutes and rules so righteous as all this law that I set before you today?”
Paul describes this separating function in Ephesians 2:14-15, where he speaks of Jesus “breaking down in his flesh the dividing wall of hostility by abolishing the law of commandments expressed in ordinances.” The law created a barrier between Jew and Gentile—a barrier that served God’s purposes for a time but was removed in Jesus so that both groups could be united in one body.
To Preserve Israel Until the Messiah Came
The law functioned as a preservative, keeping Israel intact as an identifiable nation until Jesus arrived. The strict regulations about marriage, diet, and religious practice prevented Israel from being absorbed into surrounding cultures. This was essential because God’s promises required a continuing nation of Israel through whom the Messiah would come.
God had promised Abraham that through his seed all nations would be blessed (Genesis 12:3). That seed was ultimately Jesus (Galatians 3:16). For this promise to be fulfilled, Abraham’s descendants had to survive as a distinct people. The law, by keeping Israel separate, ensured that the nation endured through centuries of temptation toward idolatry and assimilation.
To Provide a System of Civil Government
Israel was not merely a religious community but a nation-state, and the law provided the framework for civil governance. The various case laws, regulations about property, instructions for resolving disputes, and penalties for crimes gave Israel a comprehensive legal system directly from God.
This theocratic aspect of the law was unique to Israel’s covenant relationship with God. No other nation was called to operate as a theocracy with God as their direct King. The civil laws were designed specifically for Israel in the land God gave them and were not intended to be exported wholesale to Gentile nations, though the moral principles underlying them reflect God’s universal standards of justice.
Why Believers Are No Longer Under the Law
If the law served such important purposes, why are believers today no longer under it? Because the law’s purposes have been fulfilled in Jesus. The law revealed sin; Jesus dealt with sin. The law showed our inability; Jesus provided His ability. The law pointed to Jesus; Jesus has now come. The law preserved Israel until the Messiah; the Messiah has arrived.
As Paul declares in Romans 10:4: “For Christ is the end of the law for righteousness to everyone who believes.” The Greek word for “end” (τέλος, telos) can mean both “termination” and “goal.” Jesus is both the goal toward which the law was pointing and the termination of the law as a means of seeking righteousness.
Believers today are not under the Mosaic law as a covenant but are under grace (Romans 6:14), under “the law of Christ” (Galatians 6:2), led by the Spirit (Galatians 5:18). The moral standards of God expressed in the law continue to inform Christian ethics—not because we’re under the Mosaic covenant but because those standards reflect God’s unchanging character. But the ceremonial laws have been fulfilled in Jesus, and the civil laws applied specifically to Israel as a theocratic nation.
Conclusion
The Mosaic law served multiple divine purposes: revealing God’s holy character, exposing sin, demonstrating human inability, pointing to Jesus, separating Israel from the nations, preserving Israel until Messiah came, and governing Israel as a nation. None of these purposes were failures. The law accomplished exactly what God intended. And its ultimate purpose—bringing people to Jesus for salvation by grace through faith—continues to function today whenever the law is properly proclaimed.
“So then, the law was our guardian until Christ came, in order that we might be justified by faith. But now that faith has come, we are no longer under a guardian.” Galatians 3:24-25
Bibliography
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