One of the biggest hindrances to deliverance or healing is unforgiveness.  God's Word says Luke 17:3 Take heed to yourselves: If thy brother trespass against thee, rebuke him; and if he repent, forgive him. Luke17:4 And if he trespass against thee seven times in a day, and seven times in a day turn again to thee, saying, I repent; thou shalt forgive him. KJV
When speaking with married couples, when the husband says she won’t forgive me. The wife’s response is almost always, “he’ll just do the same thing again, he always does.” Two things are happening here: 1 She is holding the husband in bondage with her words by holding a judgement against him. Our words have the power to give us what we speak. Read Proverbs 18:21
Especially if we have faith in those words.  Our words have much more power than we realize. Jesus had this to say about our
words. Mat 12:36 But I say unto you, That every idle word that men shall speak, they shall give account thereof in the day of judgment. Mat 12:37 For by thy words thou shalt be justified, and by thy words thou shalt be condemned. KJV.
2 Jesus said that if your brother sins against you seven times and came seven times in the same day to ask forgiveness 
forgive him and moreover, look what he said to Peter: Mat 18:21 Then came Peter to him, and said, Lord, how oft shall my brother sin against me, and I forgive him? till seven times? Mat 18:22 Jesus saith unto him, I say not unto thee, Until seven times: but, Until seventy times seven. KJV So, if you are the one being repeatedly offended by someone who keeps asking for forgiveness. You need to unconditionally forgive that person and make a positive confession over them. Because after all, if God Himself is forgiving you, who repeatedly sins; why would you not extend that same grace? If you are the one who
keeps offending, you need to pray for God to deliver you. Let’s continue down this path of forgiveness. I said this at the very beginning that unforgiveness is one of the main reasons that people do not receive their deliverance or healing. But does the Bible back this up? I’m glad you asked, because it does.
Mat 18:23 Therefore is the kingdom of heaven likened unto a certain king, which would take account of his servants.
Mat 18:24 And when he had begun to reckon, one was brought unto him, which owed him ten thousand talents.
Mat 18:25 But forasmuch as he had not to pay, his lord commanded him to be sold, and his wife, and children, and all that he had, and payment to be made. Mat 18:26 The servant therefore fell down, and worshipped him, saying, Lord, have patience with me, and I will pay thee all. Mat 18:27 Then the lord of that servant was moved with compassion, and loosed him, and forgave him the debt. Mat 18:28 But the same servant went out, and found one of his fellowservants, which owed him an hundred pence: and he laid hands on him, and took him by the throat, saying, Pay me that thou owest. Mat 18:29 And his fellowservant fell down at his feet, and besought him, saying, Have patience with me, and I will pay thee all. Mat 18:30 And he would not: but went and cast him into prison, till he should pay the debt. Mat 18:31 So when his fellowservants saw what was done, they were very sorry, and came and told unto their lord all that was done. Mat 18:32 Then his lord, after that he had called him, said unto him, O thou wicked servant, I forgave thee all that debt, because thou desiredst me: 
Mat 18:33 Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee?
Mat 18:34 And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him.
Mat 18:35 So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses. KJV  

Unforgiveness is an open door that can lead to demonic oppression in the form of sickness, infirmity and other bondages.
You need to spend some  time searching your heart to see if you have unforgiveness towards anyone. Take a sheet of paper and write down the names of anyone you have ever had unforgiveness towards, dead or alive. If you can’t remember, or don’t know their names you should describe them. Example: the guy that cut me off in traffic 2 days ago. Or the manager that locked the door to the supermarket early and made me come back the next day. Whatever the case, write it down and then pray a prayer of forgiveness over them, by name. When you finish praying, you need to ask God to close any door that was opened because of unforgiveness and take the right of any spirit from attacking your mind or body and from operating in your life. I would also recommend burning that list as an act of finality.

(Taken from my book "By His Stripes I am Healed")