Jesus, [when he went into the desert for 40 days of fasting after his baptism]…was actually “leaning out” his nourishment at the physical level so that his heart would be able to listen more deeply and his subtle energetic body might feast directly on the flesh and blood of the divine Word stirring to life within him. He was fine-tuning his instrument so that he would be able to catch the more subtle drift of what was awaiting him up ahead.
A fast is really training – exactly like athletic training- so that our whole embodied being can be tuned up to support a spiritual aim we wish to achieve… our physical capacity to be available to truth at a subtle and much more intense level.
~ from The Wisdom Jesus by Cynthia Bourgeault, pp. 126, 136