For years this questions troubled me. I wanted an answer. Then one day the Lord whispered in my ear, "Why are you trying so hard to clean a heart of sin? I took your heart of sin and nailed it to the cross. (Colossians 2:6-17). You need a new heart, a heart transplant."
Days later while I was reading in Ezekiel 36:25-27, my eyes were opened to the miracle that happened when I was born again,. "I will sprinkle clean water on you, and you shall be clean from all your uncleanliness, and from all your idols, I will cleanse you. 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 a NEW 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"
The light went on! The Lord Himself had created a new heart in me. No wonder I felt condemned and discouraged trying to change myself. It was impossible.
I am so grateful for the power of the cross and how it has liberated me from the power of sin. May the Name of the Lord be praised forever and ever.