God asks his people what their motives are for fasting. It’s possible to do so with a selfish reason rather than placing God at the centre of our attention.
One quickly finds in a time of fasting your motives come to the surface. The constant hamster wheel of distracting thoughts must run down. There are so many things our mind has been consuming, that we have indigestion of the soul.
John Piper said, “The greatest enemy of hunger for God is not poison but apple pie. It is not the banquet of the wicked that dulls our appetite for heaven, but endless nibbling at the table of the world. It is not the X-rated video, but the prime-time dribble of triviality we drink in every night.” 
Buddhists and Hindus may fast to reach a state of emptiness; and so should we. But once, the clutter is gone we do not enshrine emptiness. Instead, we move to being filled with God’s Spirit. As we are filled, we become those whom God has made us to be. We become ourselves in God’s Presence.
Dr. Dan Allender is a Christian counsellor who said this:
“Fasting from any nourishment, activity, involvement or pursuit—for any season—sets the stage for God to appear. Fasting is not a tool to pry wisdom out of God's hands or to force needed insight about a decision. Fasting is not a tool for gaining discipline or developing piety (whatever that might be). Instead, fasting is the bulimic act of ridding ourselves of our fullness to attune our senses to the mysteries that swirl in and around us." 
In the turning away from the mirror on ourselves, we look around for the face of God. A fasting from earthly appetites may clear the way to embrace our spiritual appetite. In fasting we place God at the center of our life.