Edawrd Farrell writes:
"Almost everywhere at all times fasting has held a place of great importance since it is closely linked with the intimate sense of religion. Perhaps this is the explanation of the demise of fasting in our day.When the sense of God diminshes, fasting disappears." (In John Piper, A Hunger for God: Desiring God through Fasting and Prayer)
This explains why, when I teach on biblical fasting, I first teach about the preence of God, and entering into that presence.
First: abide in Christ. Forcus on Jesus. Dwell in Him. Enter into the Big Dance (the Trinitarian perichoretic union).
A main way to abide in Christ is to pray. prayer is talking with God about what you and He are doing together. You speak to God, and God speaks to you.
As you become aware of the grievous sacred moments of life God may issue a call for you to fast and pray, focusing your prayers and energies towards God on behalf of the grievous moment. In this way fasting emerges out of the God-relationship.