There is a perception that we should fast when we want something, as though the act of fasting somehow appeases God, and seeing us “suffer” gets Him to grant our request. Nothing can be further from the truth. It is not our fasting that pleases God, it is the fruits of our fast (provided we fast in the proper mind set, and do not merely diet) that please Him. We fast, not to get what we want, but to prepare ourselves to receive what God wants to give us.
The purpose of fasting is to bring us more in line with another Mary, the sister of Lazarus, and away from their sister Martha, who in the famous passage was “anxious and troubled about many things.” Fasting is intended to bring us to the realization of “the one thing needful.” It is to help us put God first and our own desires second, if not last. As such it serves to prepare us to be instruments of God’s will, as with Moses in his flight from Egypt and on Mt. Sinai, as well as our Lord’s fast in the wilderness. Fasting turns us away from ourselves and toward God. In essence it helps us become like the Theotokos, an obedient servant of God, who heard His word and kept it better than anyone else has or could.
From Pravmir- http://t.co/rgNU6a3M5M