The answer
Through fasting, we declare the desire of our hearts to partake with our Christ in His sacrificial love. When the believer feels hungry or thirsty, he offers a sacrifice of thanksgiving to God who allowed him to partake in His cross or in His sacrificial love, and at the same time God inhales this sacrifice as a soothing aroma.
St. John Cassian says, “The duty of fasting becomes acceptable before God when it is perfected with the fruits of love.”
And St. Evagrius says, “When the soul desires to seek after a variety of foods then it is time to afflict it with bread and water that it may learn to be grateful for a mere morsel of bread.”433
Fr. Tadros Yacoub Malaty
Notes
433 St. Evagrius of Pontus, Evagrius Ponticus: The Praktikos. Chapters on Prayer, trans., John Eudes Bamberger (Cistercian Publications, 1972) 16: p. 21.