And I will give them one heart, and a new spirit I will put within them. I will remove the heart of stone from their flesh and give them a heart of flesh, that they may walk in my statutes and keep my rules and obey them. And they shall be my people, and I will be their God. Ezek. 11:19-20
And I will give you a new heart, and a new spirit I will put within you. And I will remove the heart of stone from your flesh and give you a heart of flesh. And I will put my Spirit within you, and cause you to walk in my statutes and be careful to obey my rules. Ezek. 36:26-27
In the book of Ezekiel, God foretells the judgement of Israel, Judah, and the surrounding kingdoms, as none of those people have obeyed him. However, in the passages above, he offers some encouragement: Some people will remain. While the kingdoms may be destroyed, there will still be some people that are faithful. Since his people continue to disobey him, to have hearts of stone, God says that he will replace those stone hearts with hearts of flesh. Just as a heart of stone brings death and a heart of flesh brings life, God will bring spiritual life to those who are dead. And not only will they have a new desire to serve God, but the spirit of God himself will live in them.
I think we can apply the message to individuals as well: If we follow God, it is because God spiritually re-birthed us, has given us a new heart, a new will, that wants to follow the way of life that he wishes for us. And we have the power of God living inside us!