There is a kind of unbelief that only comes out by prayer and fasting. It is the kind of unbelief prompted by pride or reliance on self. The connection between fasting and humbling one's self is found in Psalm 35:13 ("But as for me, when they were sick, my clothing was sackcloth: I humbled my soul with fasting; and my prayer returned into mine own bosom.") Fasting or self-denial—telling your body "no"—will humble your soul because it takes your agenda and submits it to God's.

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