It is the spirit that is moving our frozen hearts and melting into us the love of God. This love is a fire and can cause us the same type of pain. that is felt when we come in from the cold. But we must leave the frozen old selves to become one in God's loving design.
And what of those who are determined to do it by their own self, (without the aide of God's Grace)? They will find that the battle against sin waged outside of Christ is a cycle built on addiction and no recovery.
You can for awhile build an addiction to accomplishment, but these efforts will become cold; thinking that you have conquered the sin you will go back again to your old ways. The feeling of failure will become greater and greater till one day you no longer attempt to stop yourself from your natural desires.
The natural desires of sin are built on a law of diminishing returns. The enjoyment that ones gets from sinning will become more and more dissatisfying. The only satisfaction to cure the Christ shaped hole in your heart is to repent and allow the Holy Spirit to lead you in this life.
Reflections From Reading John Owens the Mortificiation of Sin Chapter 3 Tomorrow Chapter 4 of John Owens Mortification of Sin.