Normally when a person looses his appetite and does not desire food consistently for a period of time, it is generally considered that he or she is ill and medical attention is sought.
So it is with the Christian when he looses his appetite for the things of God. This is an indication that something is wrong in the heart of that individual to cause him to turn away from spiritual things. The Christian who loves God and is in right fellowship with him has a hunger and thirst for the things of God that cannot be satisfied until he is spending his time in the word of God, in prayer and meditation, and in fellowship with God's people.
“Blessed are they which do hunger and thirst after righteousness: for they shall be filled.” Matthew 5: 6. “Woe unto you that are full for ye shall hunger. Woe to you that laugh now! for ye shall mourn and weep.” Luke 6: 25.
“The full soul loatheth an honeycomb: but to the hungry soul every bitter thing is sweet. Proverbs 27: 7.