Introduction Jeremiah 31:31-34 is one of the most important passages in the Old Testament, a passage the writer of Hebrews quotes at length to explain why the gospel is better than the old law. Jeremiah prophesied during the dark days before the Babylonian exile, when the people had repeatedly broken the covenant God made with their fathers. Out of that judgment comes this glorious promise: God himself would establish a new covenant, not like the one broken at Sinai. This passage teaches us that salvation is entirely of God -- from initiation to completion. The Reformed tradition has rightly treasured these verses as a cornerstone of the doctrine of grace. Verse 31 -- Behold, the Days Come "Behold, the days come, saith the Lord, that I will make a new covenant with the house of Israel, and with the house of Judah." The opening word "Behold" calls us to pay attention. God announces something unprecedented. He will make a "new covenant" -- not merely renew the old one, but establish something fundamentally different. The old covenant was external, written on tablets of stone, dependent upon the people's obedience. But Israel and Judah had both failed. The new covenant would not depend on man's faithfulness to God, but on God's faithfulness to man. This is the covenant of grace, unilateral in its origin, effectual in its execution. As the Westminster Confession of Faith teaches, the covenant of grace was administered differently in the Old and New Testaments, but it is the same covenant, promising the same salvation in Christ. Verse 32 -- Not According to the Covenant Made with Their Fathers "Not according to the covenant that I made with their fathers in the day that I took them by the hand to bring them out of the land of Egypt; which my covenant they brake, although I was an husband unto them, saith the Lord." The contrast is explicit. The Mosaic covenant was a covenant of works in its administration -- "Do this and live." The people broke it. God calls himself their "husband" -- a word of covenant love and faithfulness -- yet they were adulterous. The old covenant exposed sin but could not cure it. It demanded righteousness but did not provide it. Paul would later write that the law was a schoolmaster to bring us to Christ. The law could condemn; only grace could convert. Verse 33 -- I Will Put My Law in Their Inward Parts "But this shall be the covenant that I will make with the house of Israel; After those days, saith the Lord, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people." Here is the heart of the promise. The law moves from stone to flesh, from external command to internal desire. This is regeneration -- the new birth. God does not merely tell his people what to do; he makes them "willing in the day of his power" (Psalm 110:3). The law written on the heart means that God's people will love what he loves and hate what he hates. This is the fulfillment of the covenant promise: "I will be their God, and they shall be my people." Not because they chose him, but because he chose them. Verse 34 -- They Shall Teach No More Every Man His Neighbor "And they shall teach no more every man his neighbour, and every man his brother, saying, Know the Lord: for they shall all know me, from the least of them unto the greatest of them, saith the Lord: for I will forgive their iniquity, and I will remember their sins no more." The knowledge of God in the new covenant is not merely informational but relational. Every believer -- from the least to the greatest -- has a true, saving knowledge of the Lord. This is the priesthood of all believers, anticipated here in Jeremiah. And the foundation of this covenant is forgiveness: "I will forgive their iniquity, and I will remember their sins no more." God's "not remembering" is not divine forgetfulness but covenantal promise. He will not hold these sins against his people. This is the gospel: sins forgiven, remembered no more, because the Lamb of God has borne them away. Conclusion The new covenant is the covenant of grace, established by the blood of Christ, applied by the Holy Spirit. It is not dependent upon our faithfulness but upon God's. And because it is God's work, it cannot fail. Every promise here is "yes" in Christ Jesus. Application Questions: 1. How does Jeremiah's promise of the new covenant help you understand why your own efforts at self-reformation are never enough? 2. What difference does it make in your daily life to know that God's law is written on your heart by the Spirit, not merely commanded from outside? 3. How does the promise that God will "remember your sins no more" change the way you respond to past failures and present temptation?