For as he thinketh in his heart, so is he............... (Proverbs 23:7a KJV)
A good man out of the good treasure of the heart bringeth forth good things: and an evil man out of the evil treasure bringeth forth evil things. (Matthew 12:35 KJV)
Your life is reflecting the 'treasures' of your heart (mind). The first scripture says that a man's thought life is actually who he is. If not currently, give it time, it will manifest. This is why the prayer of agreement should not be rushed into. You must search the thoughts of the heart of who you are dealing with and make sure they are aligned with yours. Why? Because of the second scripture.
Let's put it this way, success comes from within and failure comes from the inside. Don't blame anybody for your failure, certainly not where healing is concerned, you will be abdicating your responsibility. Healing is on the inside , focus on it and push it out. No this is not mind over matter, this is pure Holy Ghost. You are basing it on the promises of God, not some wishy-washy, mamby-pamby nonsense.
If you are going to overcome sickness or disease, you must first see it on the inside. Spend time thinking good thoughts see yourself on the inside the way God sees you.Let the well of water build up from inside of you, overcome all the obstacles on the inside first.
Again I say this is not mind over matter, IT IS HAVING YOUR MIND OVER WHAT REALLY MATTERS. This is why praise and thanksgiving is so powerful. True praise and thanks giving sets your mind on the reward. You cannot be praising and giving thanks and not have victory set on your mind.
Once your thinking is right your speaking will be right and your acting will be right, healing will follow like day after night.
WHERE THE MIND GOES, SO FOLLOWS THE MAN