Why did God give Israel the law at Sinai?
The law was not a ladder Israel climbed to earn God's favor; it was given to people God had already redeemed from Egypt. Spoken from the smoking mountain, it formed a rescued mob into a covenant nation and revealed the holy character of the God who saved them. Jesus did not abolish it but fulfilled it, and under the new covenant its deepest demand is written not on stone but on hearts.
This question arose from studying What does the Exodus show us about God?.
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What the Scripture says
Redemption came first; the law second
Before a single commandment sounds, God identifies Himself as Redeemer: 'I am Yahweh your God, who brought you out of the land of Egypt, out of the house of bondage.' The order is everything. Israel is not saved because they kept the law; they receive the law because they are saved. Grace precedes obligation at Sinai just as it does in the gospel, which is why obedience answers deliverance instead of purchasing it.
“I am Yahweh your God, who brought you out of the land of Egypt, out of the house of bondage.
‘You have seen what I did to the Egyptians, and how I bore you on eagles’ wings, and brought you to myself.
A covenant constitution revealing God's character
God offers Israel a calling before He gives them rules: if they obey His voice they will be 'my own possession from among all peoples', 'a kingdom of priests, and a holy nation'. Each commandment then shows what holiness looks like in daily life, since it mirrors the character of the One who spoke it. The law is less a fence around Israel than a portrait of God, drawn for a nation meant to display Him.
Now therefore, if you will indeed obey my voice, and keep my covenant, then you shall be my own possession from among all peoples; for all the earth is mine;
and you shall be to me a kingdom of priests, and a holy nation.’ These are the words which you shall speak to the children of Israel.”
The terrifying mountain and the mediator
At Sinai there were 'thunders and lightnings' and 'the whole mountain quaked greatly'. The people begged Moses, 'Speak with us yourself, and we will listen; but don’t let God speak with us, lest we die.' The fear taught them that sinners cannot stand unmediated before absolute holiness. Yet Moses answers, 'Don’t be afraid, for God has come to test you'; reverence and trust were meant to stand together. The whole scene cries out for a better Mediator.
On the third day, when it was morning, there were thunders and lightnings, and a thick cloud on the mountain, and the sound of an exceedingly loud trumpet; and all the people who were in the camp trembled.
Mount Sinai, all it, smoked, because Yahweh descended on it in fire; and its smoke ascended like the smoke of a furnace, and the whole mountain quaked greatly.
They said to Moses, “Speak with us yourself, and we will listen; but don’t let God speak with us, lest we die.”
Moses said to the people, “Don’t be afraid, for God has come to test you, and that his fear may be before you, that you won’t sin.”
Jesus fulfills, He does not abolish
Jesus says plainly, 'I didn’t come to destroy, but to fulfill.' Then, in the rest of the Sermon on the Mount, He deepens every commandment until it reaches the heart: murder becomes hatred, adultery becomes lust, and the standard rises to 'just as your Father in heaven is perfect.' Paul agrees that faith does not cancel the law but establishes it, because in Christ the law finds what it always aimed at: a righteousness God gives, not merely commands.
“Don’t think that I came to destroy the law or the prophets. I didn’t come to destroy, but to fulfill.
Therefore you shall be perfect, just as your Father in heaven is perfect.
Do we then nullify the law through faith? May it never be! No, we establish the law.
The law as tutor, and the promise written on hearts
Paul calls the law a guardian for God's children on the way to maturity: 'the law has become our tutor to bring us to Christ'. By exposing sin it drove Israel, and drives us, toward the promised remedy. That remedy is the new covenant, where God pledges, 'I will put my law in their inward parts, and in their heart will I write it'. The same law, once carved on stone tablets below the smoking mountain, comes home to the heart by the Spirit.
So that the law has become our tutor to bring us to Christ, that we might be justified by faith.
But now that faith has come, we are no longer under a tutor.
But this is the covenant that I will make with the house of Israel after those days, says Yahweh: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people:
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What was the tabernacle for?→“Let them make me a sanctuary, that I may dwell among them. According to all that I show you, the pattern of the tabernacle, and the pattern of all of its furniture, even so you shall make it.”What did the sacrificial system teach Israel?→“For the life of the flesh is in the blood; and I have given it to you on the altar to make atonement for your souls: for it is the blood that makes atonement by reason of the life.”Explore further
Does James contradict Paul? Is it faith or works?→Our Walk with Him trail“for by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, that no one would boast. For we are his workmanship, created in Christ Jesus for good works, which God prepared before that we would walk in them.”How is the new covenant different from the old one?→Jesus Christ trail“But this is the covenant that I will make with the house of Israel after those days, says Yahweh: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people: and they shall teach no more every man his neighbor, and every man his brother, saying, Know Yahweh; for they shall all know me, from their least to their greatest, says Yahweh: for I will forgive their iniquity, and their sin will I remember no more.”Hold onto these
Verses to meditate on
“I am Yahweh your God, who brought you out of the land of Egypt, out of the house of bondage.
Now therefore, if you will indeed obey my voice, and keep my covenant, then you shall be my own possession from among all peoples; for all the earth is mine; and you shall be to me a kingdom of priests, and a holy nation.’ These are the words which you shall speak to the children of Israel.”
“Don’t think that I came to destroy the law or the prophets. I didn’t come to destroy, but to fulfill.
So that the law has become our tutor to bring us to Christ, that we might be justified by faith.
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