Mark 9:24

Immediately the father of the boy cried out (with a desperate cry), saying “I do believe; help (me overcome) my unbelief.”

We can have faith and still be in unbelief, especially if the circumstance is larger in our eyes than Jesus, our savior. Jesus needs us to transfer our focus back to Him and prioritize thoughts of the Word over thoughts of the circumstance. The mind will play like a ball bouncing back and forth if we doubt, and we will be double-minded. Belief comes from not having doubts that God can perform all that He has promised us in the Bible.