Another great passage from John Piper’s wonderful book on Fasting: A Hunger for God, in which Piper draws on a powerful quote from John Wesley to explain how fasting both expresses AND assists a deep hunger for God in our lives:
One of the great effects of fasting is that it assists what it expresses. I mean that fasting is mainly an expression of the soul’s hunger for God. It is not a contrived means to make us love God. We love him and long for him. And then fasting rises up as a way of saying earnestly with our whole body what our hearts feel: I hunger for you, O God. Fasting expresses, rather than creates, hunger for God.
Nevertheless, it is also true that the very nature of fasting makes it an assistant to this hunger for God. The reason is that hunger for God is spiritual, not physical. And we are less sensitive to spiritual appetites when we are in the bondage of physical ones. This means that fasting is a way of awakening us to latent spiritual appetites by pushing the domination of physical forces from the center of our lives. John Wesley expressed this as well as anyone I have read. What he calls the “sensualizing” of the soul is a great hindrance to our longing for Jesus to return. Therefore fasting assists the very experience of hunger for God that it also expresses.
Fullness of bread [increases] not only carelessness and levity of spirit, but also foolish and unholy desires, yea, unclean and vile affections. . . . Even a genteel, regular sensuality is continually sensualizing the soul, and sinking it into a level with the beasts that perish. It cannot be expressed what an effect a variety and delicacy of food have on the mind as well as the body; making it just ripe for every pleasure of sense, as soon as opportunity shall invite.
Therefore, on this ground also, every wise man will refrain his soul, and keep it low; will wean it more and more from all those indulgences of the inferior appetites, which naturally tend to chain it down to earth, and to pollute as well as debase it. Here is another perpetual reason for fasting; to remove the food of lust and sensuality, to withdraw the incentives of foolish and hurtful desires, of vile and vain affections.
I do not mean to belittle the good gifts of God, as if eating were an evil or even a hindrance to spiritual sensitivity. Together with Wesley I simply mean to say that most of us run the risk of being overly “sensualized” simply by having every craving satisfied and rarely pausing in a moment of self-denial to discover if there are alive within us spiritual appetites that could satisfy us at a much deeper level than food, and that are designed for the honor of God. Such is the appetite for the coming of King Jesus.
A Hunger for God, Crossway, 1997. pp. 89 – 91