Do you have a hunger for God? If we don’t feel strong desires for the manifestation of the glory of God, it is not because we have drunk deeply and are satisfied. It is because we have nibbled so long at the table of the world. Our soul is stuffed with small things, and there is no room for the great. If we are full of what the world offers, then perhaps a fast might express, or even increase, our soul’s appetite for God. Between the dangers of self-denial and self-indulgence is the path of pleasant pain called fasting.
– John Piper –