This does not contradict Deuteronomy 30:6, where it is said that "the LORD your God will circumcise your heart." It is instead a clarification. The changing, the growing, the overcoming, the transformation of the heart, the writing of the laws on the heart, is cooperative. God does His part; we do our part. If God would do everything, then what would be the need of removing the fault? Why do it? God removes the fault so that we can do our part! It is a cooperative effort.
How does God do His part? He calls us and gives us His Spirit. As John 14 tells us, the Spirit shall be with you and in you. The goodness of God by His Spirit leads us to repentance (Romans 2:4). So God calls and opens up the mind, working with us by His Spirit in a way that He never did before. He makes things mean more to us in a far deeper and more meaningful way. He provides us with greater understanding and more passion so we desire to yield to Him. He begins His miraculous work of changing our hearts.
What remains to be seen is what will we do with this altered situation? He does His part by giving us knowledge and increasing our faith. He reveals to us the true Christ, His law, and what the purpose of life is. He spurs an interest in His Word that we never had before. What are we going to do? We must respond. As we respond, changes begin to take place.
Sometimes, Israel's attitude toward God was good, and He delighted in it. However, they could never sustain it. In the book of Judges, when Israel had an outstanding leader like Gideon, things went along smoothly for a good while. But Gideon died, and the country went downhill. God had to raise up another leader. Such is the gist of the historical relationship between God and Israel.
We have had relationships with people that were similar—good for a little while, bad for a long while, good for a little while, bad for a long while. However, God does not want to marry someone about whom He must always worry whether or not He must fight with them. He wants to have a marriage with someone like Him—who thinks as He does, whom He can really be "one" with. He does not want a relationship that is "hot" one minute and "cold" the next, nor one in which the couple throws their arms around each other and everything is warm and fuzzy, but in an instant, one is giving the other the cold shoulder.
That is the kind of relationship He had with Israel. He does not want that kind of a relationship with the "Israel of God" (Galatians 6:16). Thus, there must be a cooperative effort between God and the believer to change our hearts.