Illumined in our souls through abstinence, let us venerate the saving cross upon which Christ was nailed, and let us cry aloud to it: Hail the delight and sure help of those that fast; Hail, destroyer of the passions, adversary of the devils; Hail blessed wood! (Matins Sessional Hymn, Tone 8, from the Triodion, Tuesday in the 4th week of Great Lent)
Why do we fast? If a person fasts because it is a rule, he does not understand- he is not “illumined”. We fast precisely because of the human condition, which needs fasting in order to be “illumined”. This is a biological/spiritual “law”, as binding upon the human body and soul as, for instance, the law that if one drinks a liter of alcohol they will not be able to reason well, or if more calories are ingested than are used in activity, a person will become fat.
There is a connection between the body and soul; each affects the other. We do not understand how this interaction occurs, but we know from experience various ways that each affects the other. …