31-32 Behold, the days are coming, declares the Lord, when I will make a new covenant with the house of Israel and the house of Judah, not like the covenant that I made with their fathers on the day when I took them by the hand to bring them out of the land of Egypt; my covenant that they broke, though I was their husband, declares the Lord. 

33 But this is the 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. 34 And no longer shall each one teach his neighbour and each his brother, saying, ‘Know 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. Jeremiah 31:31-34 (English Standard Version)

When people repeat something it's usually because they consider it to be important. Four times in these four verses Jeremiah says 'declares the Lord!'. He wanted those who heard his message to know it wasn't something he had made up, but it was what God had told him to tell them. What was this important promise from God? (vs 31-32)

It was the promise of a fresh covenant. A covenant is like a treaty, but a treaty is often a contract made from both sides and each party sets their terms. But in this covenant it's God who takes the initiative and He promises to do something wonderful. Looking at vs 33-34 can you see at least four amazing things God said this new covenant would result in?

He said that He would cause them to know His gracious laws in their hearts. They would be His special people. Even the least of them would have a personal relationship with Him and would not depend on other people to be a go-between for them. Best of all, God would put their failures and sins behind Him. What a precious covenant this was. But how would it be made possible? Surely if God is holy He can't just overlook sin as if it doesn't matter.

When Jesus ate the meal (called ‘the Passover’) with His disciples – the last one He had with them before His crucifixion – He said something very significant. Luke’s gospel tells us that “Jesus took bread, and when He had given thanks, broke it, and gave it to the disciples, saying, 'This is my body, which is given for you. Do this in remembrance of me.' And likewise the cup after they had eaten, saying, 'This cup that is poured out for you is the new covenant in my blood.'” (Luke 22:19-20) Those words are just one of at least nine references in the New Testament to Jeremiah's four verses of what the Lord had declared.

A good example of these verses is what the New Testament writer of the book called Hebrews wrote. Writing to Jewish people in his day he said: “Every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. But when Christ had offered for all time a single sacrifice for sins, He sat down at the right hand of God, waiting from that time until his enemies should be made a footstool for his feet. For by a single offering he has perfected for all time those who are being sanctified. And the Holy Spirit also bears witness to us. For after saying: 'This is the covenant that I will make with them after those days, declares the Lord, I will put my laws on their hearts, and write them on their minds', He then adds: ‘I will remember their sins and their lawless deeds no more.' So where there is forgiveness of these, there is no longer any offering for sin!” (Hebrews 10:11-18)

The reason God can put our sins out of His sight is because the Lord Jesus Christ sealed God's wonderful New Covenant with His own blood that He shed for sinners. And it's because those who believe on Christ are made clean and holy by that sacrifice, that they are set apart (sanctified) for God to live within them, and to have that personal relationship and promise of eternal life. The gospel is a message that calls sinners to experience God's covenant of salvation.