With Lent approaching fast, it is perhaps particularly important to give some thought to the topic of fasting and—more importantly—ascesis. The Church from Her earliest days—as is evident from the Didache—has prescribed particular days and times when one is expected to fast. Why is it that we fast, what is the point of it and what is its benefit?
One error which has to be dispelled is that fasting is a Church-prescribed a diet. There have been more than enough people who have argued for fasting because "it's good to take a break from red meat." Fasting is not a diet and it is not a Church-sanctioned juice cleanse. This is not to say that it may not produce good results for the body, rather that it was instituted precisely for the opposite purpose, to stop us from focusing on the body.
The Church denotes fasting and other similar practices as ascesis, or 'exercise' in Greek, referring to the training necessary for an authentic Christian life. Thus, an important caveat is that the point of fasting is not to just eat the "right" type of food. I am reminded of a middle-aged Greek gentleman who was exuberant about his strict adherence to the Orthodox rules of fasting, especially since seafood is always allowed and he had taken up the practice of having lobster at least once a week. The poor man never spent so much time thinking about food, and not about God, as during Lent!
Ascesis has two main goals: to help us grow in self-control and to encourage us to exchange the time we gain from cooking simpler meals and consuming less food for more time in prayer. The benefit which these goals bring seems rather obvious, but the depth of wisdom which the Church has on this matter goes beyond the obvious surface.
On a superficial level, it comes as a shock to no one that self-control in general is a good thing and more self-control is always a gain. Being an addict is a tedious and pleasureless activity. In fact, if you want to find out whether you're addicted to any one particular thing, resolve to not have any contact with it for a week and see if you can make it through (and perhaps that might give you a better idea of what you should give up for Lent). Because addiction stamps out pleasure, self-control is necessary not only for a balanced and virtuous life, but as the condition of possibility for obtaining pleasure in the first place.
The Greek fathers termed the product of an ascetic life as 'dispassion.' This word entered the Christian milieu through Stoic philosophy, which aimed at establishing self-control through extinguishing desires (or passions) relating to the external world. Its Christian usage, however, is slightly different. Discussion on this topic in the East reached its zenith in the storied debate between St. Gregory Palamas and Barlaam in the fourteenth century. Accused that Byzantine asceticism sought the suppression of the passions, St. Gregory responded, "But, philosopher, we have not been taught that dispassion is the putting to death of the soul’s passionate part; on the contrary, it is the conversion of the passionate part from the lower to the higher, and its active devotion to divine realities, completely turned away from evil and towards what is good." The point of ascetic practice—unlike in the case of the Stoics—is not about curbing desire because it is inherently dangerous.
Rather, it is about getting us to realize what is truly important, in the transition from the first goal to the second. Christians affirm that all of creation is good and made for our enjoyment, but we will derive no enjoyment from it unless we view it correctly. We cannot view it correctly unless we exchange our own fallen lenses with God's perfect ones, which is achieved through prayer and devotion to God. The reason why the Church has placed these practices, therefore, is neither to offer us a diet, nor because She has corporate interests in the fishing industry, but to get us to pull back and attempt to exchange appetite for particular things with appetite for God. Like fine spices, God does not detract from our enjoyment of the world, but rather directs us to enjoy it as He intended, which is to say, to enjoy it fully.