(1 Thessalonians 4:3): "For this is the will of God, even your sanctification, that ye should abstain from fornication".
(Romans 6:6): "Knowing this, that our old man is crucified with him, that the body of sin might be destroyed, that henceforth we should not serve sin".
Simply means Seperating yourself for God. See, if you will grow Spiritually, love the things of God and be free from sin, and Have a Breakthrough in life, you needed to be HONEST to yourself and ask God to search you.
According to Psalm 51, the bible reading and prayers for the fast. At this point, Let heaven search you and break you down since the day your mother gave birth to you. Anything you have done atall that is always giving you sleepless night and make you to have guilty conscience most times. Table them before God and ask him for forgiveness be honest and be sincere, no one will judge you but judge yourself and ask God just for mercy today.
First step to breakthrough is being sincere to YOURSELF and clear away hinderances to Prayers.
By doing this, sin will start irritating you because the body of sin in your life will be crusified and God will SANTIFY you today and have Mercy on your Past that is Dealing with your present.