Christians do not engage in this battling of the passions merely for the sake of askesis. And we certainly don’t do so on the basis of some sort of “works righteousness,” as though by our efforts alone we can make any real change in ourselves. It’s like asking a person covered in grime and dirt and grit to clean to a dazzling whiteness a bunch of oil-soaked rags with the scourings of a grease trap. It’s ludicrous.
Yet, our Lord expects us to fast. St. Paul says we are saved for the very purpose of doing good works, which God has already prepared for us to do. So we Christians fast and pray and give alms. And we do it toward one and only one final end. In a word, theosis, or, to use another turn of phrase, hypostatic union with God in Christ.
This union effects the transfiguration of soul and body. We do not believe that salvation is merely, or even mostly, about a declared change of status, though certainly our status is changed once we begin to be saved. Rather salvation is a transformation of our souls and spirits, as well as our bodies. We fast, we deny the body certain natural goods, not because we want to punish the body, but because we must, by God’s energetic grace, free the body from slavery to its own passions and lusts and desires. We must teach the body that there is greater, more lasting food, indeed, the bread of immortality, of which it must partake. And in the consumption of the Body and Blood of Jesus, we take into ourselves in a reality utterly mystical, which is to say, utterly more real than earthly food, which transfigures us in body and soul. Because Christ’s body has been santified in his Resurrection, and through his body, ours, our bodies must participate in this sanctification he has wrought. We do so through the means he has given us: fasting, prayer and almsgiving, sacraments of Baptism and Chrismation, consumption of the Holy Gifts in the Eucharist, and so forth.
And so, as we increase in “spiritual” virtues, our bodies themselves are also divinized. Though cloaked in, to mortal sight, ugliness and wretchedness, these bodies carry the treasure of the Holy Spirit, as it were, in humble clay jars. And through the weakness of the mortal tabernacle, the deification of soul and body is revealed in these clay vessels. This is why not a few saints’ bodies have remained incorrupt after their death. The “principle of theosis” was at work transfiguring not only their souls but their physical bodies as well.
I am unnecessarily stressing the bodily aspect of theosis here only to make the point of the totality of transformatioin that the struggle in the unseen warfare brings through the transforming grace of the Holy Trinity. We are not only persons who do not covet, or bite and devour one another, our bodies take their food, quite literally, from union in Christ Jesus with the God and Father of All. We fast because it teaches our body truths it does not, and maybe cannot, learn any other way. But our fasting is not merely about bodily transformation. Ours must not be the fasts condemned by Isaiah and our Lord. But neither can our fasting be only about inner transformation. We are whole persons.
It is as whole persons that we are united to God in Christ. And in that union, we are united to one another here in the Church Militant, as well as to the saints who live as the Church Triumphant, for we are all one Church. Our union is accomplished when our local Liturgies are made to ascend to the heavenly of heavenlies and there our dozens of worshippers are joined simultaneously in a timeless reality with all the other Faithful around the world and in heaven.
This is why we keep vigil over our thoughts, why we mortify our will in obedience to another, why we fast and pray. We seek the end of all this warfare in union with God and his saints.