It is my belief that one should eat just so much that after a meal one feels like praying.

St. Silouan the Athonite

It is required that not only with the body should we fast, but with the soul. Now the soul is humbled when it does not follow wicked opinions, but feeds on becoming virtues. For virtues and vices are the food of the soul, and it can eat either of these two. Bend your appetite toward virtues, as Paul says, "Being nourished by the word of truth."

St. Athanasios of Alexandria