The following quote by John Piper challenges us to test our love and devotion to God through abstaining from food. Are we, like our Christ, hungry enough for God to spend time with Him rather than eat? As we do this by faith, we can be sure to experience the transformation Piper speaks of in the first sentence of the second paragraph.
“What are we slaves to? What are we most hungry for – food or God? Fasting is God’s testing ground – and healing ground. Will we murmur as the Israelites murmured in the absence of break? For Jesus [when tempted by Satan in the wilderness] the question was: Would he leave the paths of sacrificial obedience and turn stones into bread? Or would he ‘live by every word that proceeds out of the mouth of God’? Fasting is a way of revealing to ourselves and confessing to our God what is in our hearts. Where do we find our deepest satisfaction – in God or in his gifts?
“And the aim of fasting is that we come to rely less on food and more on God. That’s the meaning of the words in Matthew 4:4, ‘Man shall not live on bread alone, but on every word that proceeds from the mouth of God.’ Every time we fast we are saying with Jesus, ‘Not by bread alone, but by you, Lord. Not by bread alone, but by you, Lord.’” – John Piper, A Hunger for God: Desiring God through Fasting and Prayer (pp. 58-59)