Faith in the heart can override the doubt that tries to set up in your mind.
But, Faith In the mind will not produce if doubt is in the heart.
The forces that change things in this life flow from the heart.
When you change the production of the heart, the mind doesn’t have to throw you off unless you let it. Once Faith drops down into your heart, through diligent efforts, then you must remain the gatekeeper of your mind. Don’t let your mind spin off out of control, bring it into subject to what your heart knows.
Proverbs 4:23
Keep thy heart with all diligence, for out of it are the outflowings of life