The Covenant Fulfilled | Jeremiah 31:31-34 & Luke 22:14-23 | New Hearts, New Covenant
God’s promise of a new covenant goes deeper than new rules—it gives new hearts. In Jesus, the covenant is sealed by His blood, ending the cycle of repeated sacrifices and securing a once-for-all forgiveness. Because of Christ, God declares: “I will remember their sin no more.” This message connects Jeremiah’s promise to the Lord’s Supper and invites us to live with assurance, freedom, and holiness.
📖 Click to Show the Transcript of this Sermon
Thank you for joining us for this week's sermon from First Reformed Church in Edgerton, Minnesota. Each week, we dig into God's word, trusting that the Holy spirit will continue the good work of sanctification in us. We've all heard the phrase, Forgive and forget. It's a popular idea, and it's a good one in theory. When we've done something wrong, especially something that we're genuinely sorryful for, we don't want to keep reliving it. We don't want it held against us. We don't want the people that we've wronged remembering what we've done to them. And so forgive and forget sounds like the perfect solution, right? But let's be honest. It's a pipe dream. We can forgive, but we don't forget. Even when both people genuinely want to move on, the memory of what happened doesn't just vanish. It shapes how we interact, how we trust, how we feel. The pain and the guilt don't just disappear because we say the words, I forgive you. That's what makes the promise that we see in Jeremiah 31 so astonishing. God doesn't just say, I forgive you. He says, I will remember their sin no more. It's not that he develops divine amnesia.
It's that he chooses in covenant mercy not to bring it up again. As we dig into these passages, we're going to see that the covenant that God makes with his people means that in Christ, our sins are cast as far as the east is from the west, and he remembers our sins no more. As we've been progressing through our series here of Everlasting Covenant, we've seen that God is the covenant maker and that he is the one who confirms the covenant. And the most vital thing that we need to understand about covenant is that it is God who initiates it, and it is God who secures it. And this is incredibly good news for us. Because it means that God relates to his people in a way that gives us assurance that we can grasp, assurance that we can lay hold of. And because of the very nature of the idea of covenant, we know that those promises that God gives to his people are unbreakable. And so as we drop into our passage from Jeremiah 31 today, we see a promise here of a new covenant and a clear explanation of why Why? A new one was necessary.
So if you start reading the Bible from the beginning, by the time you reach Jeremiah, the need for a new covenant has become painfully obvious. Because the story of scripture is the story of God's faithfulness, but it's also the story of human unfaithfulness. Again and again, The picture that the Bible paints is this idea of God as a faithful husband. We see that again here in Jeremiah 31. But connected to the idea of God as the faithful husband is the idea of his people being an unfaithful bride. It's a sobering image, but it's an accurate image. It gives us an easy way to understand why God promises something new for his people, why we have this idea of a new covenant. There in Jeremiah 31, Jeremiah speaks of a coming day when there will be a new covenant, not like the one made with fathers when they came out of Egypt. They broke that covenant. Even though their God was a faithful husband, they broke it. And Jeremiah is referring here when he speaks of the covenant that was given to their fathers. He was referring to the covenant at Sianai, that covenant that we looked at last week.
This was where God gave his law. And it wasn't just the Ten Commandments. It was the whole of his instruction for worship, sacrifice, and daily living. The people had agreed to it. We saw that they said, All these things we will do. But they didn't. They chased after other gods. They ignored the commands of God. They gave their hearts to idles. But yet God didn't abandon them. He doesn't say, You had your chance, and now I'm done. I'm done. Instead, he promises something better. He doesn't give them a pass, and he doesn't decide to give them a different standard of Holiness. The promise he speaks of is a covenant that transforms the heart. A covenant not written on stone tablets or scrolls, but inscribed directly onto the hearts of his people. This is the covenant that our sinful, rebellious hearts need. We need a change the inside out. That's exactly what God promises in Jeremiah 31. In verse 33, it says, This covenant that I will make with the house of Israel after those days, declares the Lord, 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.
As we come to verse 33, there's an important observation that we need to make about this new covenant. It isn't just a reboot of the original. It's not like most of the movies that we see today where there's no new ideas for stories, and so they just trot out old ones. They bring us the same franchises over and over again with a tweak to the story here or a change in the plot there. That's not what God is doing. It also isn't God putting the covenant made at Sianai on pause for a little while. The covenant that is being foretold here is so much deeper than a reboot or a temporary change of plans. It's a transformation and a renewal. God is not just giving them a list that will be easier for them to keep. He's doing something in and through them. He's giving his people new hearts. The problem wasn't the old covenant. The law was good. It showed what Holiness looked like. It showed them who God was. It displayed his character for them. The problem was humanity and our inability to keep the good and holy law of God. Repeatedly, the people rebelled against God.
They fell into corrupted worship. They fell into idolatry. The story of the Israeli over and over is that even though they had been brought out of slavery in Egypt, they were still enslaved. They were enslaved to sin. The law exposed this time time and again. They knew what the law required of them. They knew that they were to love the Lord, their God, with all their heart, soul, mind, and strength. They knew they were to love their neighbor as themselves, but they failed to do it. This is where we need to stop and we need to bring ourselves into the story. Because this isn't just a story of some ancient people who were bad at keeping God's law. This is the story of humanity after the fall. From that moment in the garden until now, humanity has been dead in trespasses and sins. We have been covenant breakers. The story of scripture shows us that it is not humanity that reaches God by our own efforts, by climbing the ladder to him through our achievements. Instead, it is God who reaches down, and he does something about the divide that our sin has created between us and him.
This is why we see God promising something better here in Jeremiah 31. He says, I will put my law within them, and I will write it on their hearts. The idea here is that this fixes the root problem, the human heart. We've all likely thought that we had something fixed and then discovered that we didn't fix the problem. We just addressed a symptom of the problem. For example, you've likely gone out to the car one morning, and the car won't start because the battery doesn't have enough juice to turn over. You assume that maybe you left some light on somewhere, you charged the battery, and it starts. But then it happens again. At this point, what do we do? We assume that our battery is bad. I don't remember when I bought it, so it must be the battery. So we plunk down the cache and you replace the battery. Everything seems good. Then your brand new battery doesn't start your car and you're late for an important meeting. The root problem was not the battery, but a faulty alternator. The battery was not the root problem. It was the problem that brought to light the real problem.
With this promise of writing the law on their hearts, God is getting doubt to the root of the problem, the human heart. He's going to plant his truth and his grace deep down in us. No longer is Holiness something that we read about or go after on our own. He is going to do a work in us as his people that gives us new hearts. We see this good news spelled out for us in Jeremiah 31: 34. It says, No longer shall each one teach his neighbor and each his brother saying, 'No, the Lord, for they shall all know me, from the least of them to the greatest, declares the Lord, for I will forgive their iniquity, and I will remember their sin no more. ' This word of the Lord that comes from Jeremiah here shows us how all-encompassing the new covenant is. It isn't just that these people who are Hebrews will now be able to say to their brother, 'know the Lord. No, they'll be able to say it to everybody. He says, says, All shall know me. ' And this isn't universalism here that everyone is saved. Instead, the idea is that people from outside of the old covenant are coming to God.
From the least to the greatest, they will know him. In other words, earthly identity markers like ethnicity, financial status, position in society, that's not what decides whether someone is a part of the family of God. Who is in the family of God are the ones that God gives a new heart. It is those that he forgives. If this idea of people outside of the family of Jacob coming to the Lord isn't surprising enough, the next statement that we read there in Jeremiah is even more surprising. He declares that he will remember their sins no more. He will truly forgive and forget. Think back. Remember the perpetual nature of sacrifices under the Old Covenant. They not only were something that were to atone for the sins of the people, but think about them and how they had to happen over and over and over again. Imagine you're a good Jewish person in the times of the Old Covenant. You go to Jerusalem, you make the trek. You sacrifice to get your family there. You bring an acceptable sacrifice of a lamb to the sacrifice. You perform all the rites and all the rituals exactly to a T as scripture commands.
At the end of the feast, what do you say to the family that you stayed with in Jerusalem during this ritual feast. See you next time. The sacrifices of the Old Covenant had to be repeated over and over, day after day. The sacrifices, not not only told them that God had shown mercy to them, but because they were being done over and over, it was a consistent reminder of their sin. They needed to be done over and over. These sacrifices He says, We're not just offered for a person or two. They were offered for all of the people, and the blood had to flow day after day, week after week, month after month, and year after year. It never ended. But the promise that we read here is that sin will be remembered no more. For people who had this repetition built into them, this has to be an astonishing promise. How can this possibly be? Well, it's only possible because at the heart of this promise of this new covenant is the truth that it's the Messiah who will come and shed his blood for the people of God. There will be a new covenant, and through him, a new way of approaching God becomes possible.
We saw that truth in what we read from Luke 22, specifically verse 20, where Jesus said, This cup that is poured out for you is the new covenant in my blood. As I've mentioned throughout this covenant series so far, these covenants are confirmed by blood. Because this showed not only the solemn nature of the commitment, but also the finality of any breaking of the covenant. It was serious business. As we come to this well-known passage here in Luke, we need to remember that same gravity. This is not just a new tradition to do at their family gatherings. It's a covenant meal, and it's looking forward to the blood that he is going to shed for the forgiveness of sins. What is being stated here, and the idea of covenant as a whole, makes it abundantly clear to us that those who might try to convince us that the cross of Jesus was not an atoning sacrifice for sin, they do not understand what is happening here. Throughout the history of the church, people have tried to do away with this idea of an atoning sacrifice. God is not that brutal. Why would God do that?
But That belief makes no sense in light of what we see here. This is the Thursday before Good Friday. These words let us know that Jesus knows the plan. There is going to be a new covenant in his blood. Covenants are made with blood. The blood spilled for a covenant has a purpose, and that purpose is to seal the deal. That's how covenants work. Jesus is going willingly because this covenant is the way by which the promise that we saw in Jeremiah is fulfilled through this new covenant. People from every tribe, tongue, and nation, that you have access to God. It also means that the continual nature of sacrifices is over. Continually offering animals that could not provide satisfaction for sin is no longer necessary because the new covenant is about the once and for all sacrifice of the perfect Lamb of God who takes away the sin of the world. Because sin is rebellion against a Holy God. The chasm between God and humanity cannot simply be waived away. A price needs to be paid for our treason against him. We can't pay that price on our own because we are sinners ourselves. No animal sacrifice can fully pay the price because it isn't our blood that is being shed.
It was the blood of goats and lambs. In order to put us in right standing with God, we needed God, the Son himself, to take on our flesh, live the perfect life that we could not live, to suffer and die and satisfy the wrath of God against our sin. In the Bible, covenants require the shedding of blood. Here, Jesus lets us know that the blood he is going to shed at the cross fulfills that requirement and establishes a new covenant. In that covenant, all of Adam's offspring are able to come to God by grace through faith. In that covenant, we do not need continual sacrifices over and over because the blood of the Lord Jesus Christ is sufficient once and for all. As I opened up, I talked about how nice it would be if we could truly forgive and forget. Our memories are always going to affect our forgiveness as humans. The covenant mercy of God, though, is so much better because the blood of Jesus means that God chooses not to remember our sins. This isn't because he's forgetful, but because the blood of the covenant covers our sins. Our sins are placed on Christ, and they are driven as far as the east is from the west, and he gives us new hearts.
This is important for us because it gives us boldness to walk in newness of life. We don't need to live in guilt and in shame because we have been truly forgiven. God has forgotten our sins. They haven't been swept under the rug or pushed off to the side until later. They are forgotten because they are no more. This doesn't minimize our sin or give us permission to commit those sins again. Instead, it means that we can boldly go to the Throne of Grace and live in light of the grace that God has blessed us with in Jesus. This is where this lands for us. This is why it's so important to understand the idea of covenant as we are living as servants of God in the 21st century. If you're in Christ, God remembers your sin no more. We don't need to walk around with the burden of guilt and shame. I'm guessing many of us have something in our lives that we can't let go of. We live as though God is holding a particular sin against us, thinking he's just waiting to use it against us. But the blood of Christ that was shed for you has a message for you.
Christ covered those sins, and God remembers them no more. If God, the offended party, doesn't remember them anymore, why should you? Why would you carry that burden when it's been released? You can walk in freedom because the covenant has been fulfilled in the work of Jesus for his people. Maybe you're here today and you live under that weight because you've never laid that sin at the foot of the cross. You've been trying to work off the guilt by doing good things, by coming to church or doing some other good work, and you haven't put your trust in the Lord Jesus Christ. The new covenant in God's grace does not call you to try harder or to do better. The call is to come and put your faith and trust in the savior who shed his blood for you. Come to him and trust in him. He alone can give you a new heart, and he can cast your sins as far as the East is from the West. Finally, Christian, the story of the fulfilled covenant of God's grace puts a call on our lives. This is the best news that there has ever been, and it is to shape how we live our lives every day.
We have been given new hearts, and so the call is to live a transformed life. We're desired to live a life that is holy, a life that is set apart to the glory of God, a life where we forgive others because God has first forgiven us. A life where we press on in faith to service to God in light of his great mercy. In the old covenant, blood was shed, and they knew they were coming back to shed more. It was a never-ending ritual that could never fully take away sin. But in the new covenant, we look to our crucified, risen, and ascended savior, and we know that his victory over sin and death means that the blood that he shed is sufficient once and for all. That means we stand up here, we leave this place, and we rest secured in his grace, and we live boldly as we walk in wholeness. The covenant has been fulfilled, and the promise that was made through Jeremiah is fulfilled. Because you've been united to Christ by faith, your sins have been forgiven. And he remembers them no more. Amen. Let us pray. Gracious God, we thank you for this imagery that we have of covenant, that it shows us the importance of what you have done.
It also shows us the finality that you make promises and you keep those promises because you are a God who cannot lie. We pray that we would live in light of this that we have new hearts, that you have taken our sin and removed it as far as the East is from the West. Help us to be a people desiring wholeness, sharing your gospel and serving others to the glory of our great Covenant King. It's in the name of Jesus that we pray. Amen. Thank you for joining us for this week's sermon. For more information about First Reformed Church, head to our Facebook page or website, edgertonfrc.org.
Key Scripture:
Jeremiah 31:31–34 — A new covenant written on the heart; “I will remember their sin no more.”
Luke 22:14–23 — “This cup…is the new covenant in my blood.”
Sermon Highlights:
The new covenant addresses the root problem—the human heart.
God’s forgiveness is covenant mercy: not divine amnesia, but His promise to remember our sins no more because they are borne by Christ.
The Lord’s Supper is not mere tradition; it points to the once-for-all sacrifice that ends repeated offerings.
Assurance flows from Christ’s finished work: we can lay down guilt and shame and walk in newness of life.
