Notice in Romans 8:7, the carnal mind is enmity against God and not subject to the law of God; neither indeed can it be. The carnal mind can't operate in God's law of faith.

Faith works in the heart. We need to understand that faith is a spiritual force. It works in the heart of man. It doesn't work in the head. Mental assent works in the head. Some mistake it for faith. But mental assent is not faith.

Mental assent working in the head says, "Yes, that's in the Bible." But they really don't believe it. If it's only in the head, you don't really believe it. Mental assent says, "Yes, it's truth, because it's the Bible."

But is it truth in your life?

"Well, no, it really isn't true in me."

Then it's not yet in your spirit.

If you have the faith of God in you, it will produce the reality of that thing. But it has to be in the spirit (heart).

Faith Won't Work In The Head
This is where so many people get into trouble. They try to operate faith out of the head. They think all they have to do is say it. They say, "Mark 11:23 says that I can have what I say, so I'm just going to start saying all these things I want."

Here is an example. A certain man said to a friend of mine, "I'll tell you, this faith confession teaching doesn't work."

He replied, "Oh, why do you say that?"

He said, "I confessed three hundred times in one day that I had a new car, and I didn't get it."

You can see all he had was the formula. He thought it was just some magic formula or something—he had the idea if you say it, the car will automatically appear in your garage.

No, that is not the way it works. That is not the application of scriptural faith. All he had was the formula. He totally missed the principle. Faith will work, but faith must be developed.

Here is something that many have never understood. Just because you believe the scripture is in the Bible does not mean the promise is going to be true in your life.  You must develop yourself in faith regarding that promise. Again, just finding something in the Bible doesn't mean you have faith to believe for it. Just saying, "I believe the Scriptures," doesn't make it come true in your life.

...faith is the substance of things hoped for....You hope for that promise to be true for you. We all hope for the promises of the Word of God to become true in our personal life, such as healing, financial prosperity and spiritual gifts.

But hope will not bring the promise into manifestation. Yet hope is needful. For without hope you won't have anything for faith to give substance to.

People come to be prayed for hoping to be healed. But hope will not heal them, because there is no substance of healing in hope. Yet, if they didn't have hope, they wouldn't come.

Many lose hope, then they have nothing for faith to give substance to. They give up too quickly.

Source: Faith and Confession by Charles Capps.
Excerpt permission granted by Harrison House Publishers