The divine work of the Lord will alter your nature by subduing the old nature, and breathing new life into you. Trust in the Lord Jesus Christ and He will take the stony heart out of your flesh, and give you a heart of flesh. Charles Spurgeon explains:
And to the one who does not work but believes in him who justifies the ungodly, his faith is counted as righteousness. . . . (Romans 4:5)
The Lord knows right well that you cannot change your own heart, and cannot cleanse your own nature; but He also knows that He can do both. He can cause the Ethiopian to change his skin, and the leopard his spots. Hear this, and be astonished: He can create you a second time; He can cause you to be born again. This is a miracle of grace, but the Holy Ghost will perform it. It would be a very wonderful thing if one could stand at the foot of the Niagara Falls, and could speak a word which should make the river Niagara begin to run up stream, and leap up that great precipice over which it now rolls in stupendous force. Nothing but the power of God could achieve that marvel; but that would be more than a fit parallel to what would take place if the course of your nature were altogether reversed. All things are possible with God. He can reverse the direction of your desires and the current of your life, and instead of going downward from God; He can make your whole being tend upward toward God. That is, in fact, what the Lord has promised to do for all who are in the covenant; and we know from Scripture that all believers are in the covenant. Let me read the words again:
A new spirit will I put within you: and I will take away the stony heart out of your flesh, and will give a heart of flesh. (Ezekiel xi.19).
What a wonderful promise! And it is yea and amen in Christ Jesus to the glory of God by us. Let us lay hold of it; accept it as true, and appropriate it to ourselves. Then shall it be fulfilled in us, and we shall have, in after days and years, to sing of that wondrous change which the sovereign grace of God has wrought in us.
It is well worthy of consideration that when the Lord takes away the stony heart, that deed is done; and when that is once done, no known power can ever take away that new heart which He gives, and that right spirit which He puts within us. “The gifts and calling of God are without repentance”; that is, without repentance on His part; He does not take away what He once has given. Let Him renew you and you will be renewed. Man’s reformations and cleanings up soon come to an end, for the dog returns to his vomit; but when God puts a new heart into us, the new heart is there forever, and never will it harden into stone again. He who made it flesh will keep it so. Herein we may rejoice and be glad forever in that which God creates in the kingdom of His grace. (All of Grace)