Fasting is the beginning and foundation of all spiritual work. Whatever you build on this foundation, therefore, becomes indestructible because it is built on solid stone. But if you lift this foundation and put in its place the satisfaction of the stomach and individual desires, all is carried away like sand by evil thoughts and the river of passions, and the whole building of virtues is destroyed. So that this may not happen to us, let us stand with joy on the firm foundation of fasting, let us be firm with our will.
St. Simeon the New Theologian
Translated by Dr. Nick Stergiou