PREPARATION FOR THE INDWELLING OF CHRIST.
Therefore God gave us a pattern of fasting in this deed,[1] so that having a desert, as it were, at the time of fasting we may abstain from feasts, pleasure and women, and so that Eve may not be joined with us so as to subvert us from chaste observance by her alluring persuasion. For he who fasts and is chaste at the time of the 40-day fast[2] seems somehow to dwell in the desert. Clearly, that certain desert is the body of a Christian when it is not filled with food or watered with drinks, but is neglected by the squalor of thirsty starvation. The desert, I say, is our body when the flesh begins to grow weaker by abstinence, when pallor is overcome by thirst, and the unadorned appearance of the whole human being becomes dirty by the contempt of material things. Then Christ the Lord dwells in the desert of our body, when he has discovered our land squalid in hunger and dry by thirst, just as that adage which the prophet David says, Just like in a deserted land where there are neither roads nor water, so I appeared in your sanctuary. For we are not able to appear to him in the sanctuary in any other way, unless the land of our body has been made desert from worldly delights and without the roads made by devilish desires and without the water from libidinous allurements. Then the Savior, dwelling in this desert of our body, conquers all the factions of the devil and makes our body his own dwelling, safe and secure from the thoughts of this age, so that we may be constituted in solitude within our very selves, as it were, and see nothing but heaven and earth. That is to say, we think about nothing other than the Lord of the heavenly kingdom and the author of the earthly resurrection.
Sermon 50a.4