Biblical faith does not operate in our minds, but rather, in our hearts. Paul wrote, “For with the heart a person believes” (Rom. 10:10a). Jesus said,
Whoever says to this mountain, “Be taken up and cast into the sea,” and does not doubt in his heart, but believes that what he says is going to happen, it shall be granted him (Mark 11:23, emphasis added).
It is quite possible to have doubts in your head but still have faith in your heart and receive what God has promised. In fact, most times when we endeavor to believe God’s promises, our minds, influenced by our physical senses and Satan’s lies, will be attacked with doubts. During those times we need to replace doubting thoughts with God’s promises and hold fast in faith without wavering.