What then is fasting for us Christians? It is our entrance and participation in that experience of Christ Himself by which He liberates us from the total dependence on food, matter, and the world . . . Yet it is only fasting that can perform that transformation, gives us the existential proof that our dependence on food and matter is not total, not absolute, that united to prayer, grace and adoration, it can itself be spiritual.
All this means that deeply understood, fasting is the only means by which man recovers his true spiritual nature. It is not a theoretical but truly a practical challenge to the great Liar who managed to convince us that we depend on bread alone and built all human knowledge, science and existence on that lie.
Fr. Alexander Schmemann
Great Lent: Journey To Pascha