The Law, sacrifices, and holiness of God
The Mosaic Covenant is foundational to understanding Israel’s identity as God’s people, their role in redemptive history, and humanity’s need for a Savior.
After centuries of slavery in Egypt, the people of Israel find themselves on the far side of the Red Sea, delivered by the mighty hand of God, who stretched out his right hand and shattered their oppressors (Ex 15:6).
The Lord had made a promise to Abraham long before, saying, “I will make of you a great nation,” and now, a family of seventy had indeed become a nation (Gen 12:2). Yet despite their growth, they were more of a ragtag band of ex-slaves than a cohesive people with an identity. At Mount Sinai, God takes the next step in his redemptive plan by entering into a covenant with Israel. This Mosaic Covenant, foundational to the story of redemption, would define their life, worship, and relationship with God.
The dramatic scene of Exodus 19 unfolds with thunder and lightning and a thick cloud on the mountain, a terrifying display of God’s holiness (Ex 19:16). The people tremble as the Lord descends. Amid this overwhelming sight, God speaks to Moses, calling Israel his treasured possession among all peoples and a kingdom of priests and a holy nation (Ex 19:5, 6). This is a high calling, but it comes with a stipulation—“if you will indeed obey my voice and keep my covenant” (Ex 19:5). The privilege of being God’s people is conditioned on their obedience to his commands.
Central to this covenant is the giving of the Law, beginning with the Ten Commandments in Exodus 20. Far from arbitrary rules, they reflect the very character of God. The first four commandments focus on Israel’s relationship with God: “You shall have no other gods before me,” “You shall not make for yourself a carved image,” “You shall not take the name of the Lord your God in vain,” and “Remember the Sabbath day, to keep it holy” (Ex 20:3, 4, 7, 8). These commandments emphasize God’s holiness, his exclusivity, and the reverence due to him.
The remaining six commandments govern relationships between people: “Honor your father and your mother,” “You shall not murder,” “You shall not commit adultery,” “You shall not steal” “You shall not bear false witness,” and “You shall not covet” (Ex 20:12-17). These laws shaped Israel into a people who reflect God’s justice and righteousness. As God himself commands, “You shall be holy, for I the Lord your God am holy” (Lev 19:2).
Yet, these Ten Commandments are only the beginning. In the following chapters, God provides detailed instructions covering every aspect of Israel’s life—justice, mercy, worship, and community relationships. This law revealed God’s righteousness and an invitation for Israel to live in fellowship with him. As Psalm 19 proclaims, “The law of the Lord is perfect, reviving the soul” (Ps 19:7). The law was a roadmap for living in a relationship with a holy God.
The law, however, also exposes the problem of sin. As Paul later writes, “I would not have known what it is to covet if the law had not said, ‘You shall not covet’” (Ro 7:7). The law serves as a mirror, revealing our sin. And with sin comes guilt, and with guilt comes the need for atonement.
Central to the Mosaic Covenant is the sacrificial system. Leviticus 17 explains the significance: “For the life of the flesh is in the blood, and I have given it for you on the altar to make atonement for your souls, for it is the blood that makes atonement” (Lev 17:11).
This system, though, was never meant to be an end in itself. As Hebrews says, “It is impossible for the blood of bulls and goats to take away sins” (Heb 10:4). The sacrifices were a shadow, pointing forward to the ultimate sacrifice—the Lamb of God who takes away the sin of the world (Jn 1:29).
The Mosaic Covenant was conditional, rooted in the principle of blessing for obedience and cursing for disobedience. As God warned, “If you faithfully obey the voice of the Lord your God, being careful to do all his commandments … the Lord your God will set you high above all the nations of the earth” (Dt 28:1). He also said, “But if you will not obey the voice of the Lord your God … all these curses shall come upon you” (Dt 28:15).
Tragically, Israel’s history, from the golden calf incident to their eventual exile, is a story of failure to keep this covenant. Paul captures this reality succinctly when he writes, “For all have sinned and fall short of the glory of God” (Ro 3:23).
This failure, however, wasn’t the end of the story. The Mosaic Covenant, with its laws and sacrifices, pointed forward to a new covenant. In Jeremiah 31, God promises, “I will put my law within them, and I will write it on their hearts. And I will be their God, and they shall be my people” (Jer 31:33). This new covenant would not rely on human obedience but on God’s grace.
Jesus, in the upper room, declared the fulfillment of this promise, saying, “This cup that is poured out for you is the new covenant in my blood” (Lk 22:20). Christ fulfilled the law perfectly. By his death, Christ redeemed us from the curse of the law by becoming a curse for us (Gal 3:13).
The Mosaic Covenant is foundational to understanding Israel’s identity as God’s people, their role in redemptive history, and humanity’s need for a Savior. As Paul explains, the law was a guardian until Christ came, revealing sin and pointing to the One who would fulfill it (Gal 3:24). As Jesus himself said, “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them” (Mt 5:17).
The shadow of Sinai looms large over the Old Testament, but its ultimate purpose is to lead us to the cross, where the demands of the law are satisfied and the promise of redemption is fulfilled. For Christ is the end of the law for righteousness to everyone who believes (Ro 10:4).