A spiritual practice that exposes the body to unpleasant sensations, in order that one may rise above the merely physical. It can include actual damage done to one's own body- as is the case with self-flagellation or the wearing of an Opus Dei-style cilice, or mere discomfort, such as the wearing of a hair shirt. Most common in monastic traditions. The religions it is most associated with are Roman Catholicism and Hinduism.

It is not masochism, because masochists enjoy what they do to themselves. As soon as a penitent or other practitioner of corporal mortification begins to enjoy the practice, he has failed. And this, of course, is the danger. Corporal mortification quickly becomes a form of pride in the body- "Look how much I can endure!"- and thus most modern practices shun it.

        Each of his senses was brought under a rigorous discipline. In order to mortify the sense of sight he made it his rule to walk in the street with downcast eyes, glancing neither to right nor left and never behind him. His eyes shunned every encounter with the eyes of women. From time to time also he balked them by a sudden effort of the will, as by lifting them suddenly in the middle of an unfinished sentence and closing the book. To mortify his hearing he exerted no control over his voice which was then breaking, neither sang nor whistled and made no attempt to flee from noises which caused him painful nervous irritation such as the sharpening of knives on the knifeboard, the gathering of cinders on the fireshovel and the twigging of the carpet. To mortify his smell was more difficult as he found in himself no instinctive repugnance to bad odours whether they were the odours of the outdoor world, such as those of dung and tar, or the odours of his own person among which he had made many curious comparisons and experiments. He found in the end that the only odour against which his sense of smell revolted was a certain stale fishy stink like that of longstanding urine: and whenever it was possible he subjected himself to this unpleasant odour. To mortify the taste he practised strict habits at table, observed to the letter all the fasts of the church and sought by distraction to divert his mind from the savours of different foods. But it was to the mortification of touch he brought the most assiduous ingenuity of inventiveness. He never consciously changed his position in bed, sat in the most uncomfortable positions, suffered patiently every itch and pain, kept away from the fire, remained on his knees all through the mass except at the gospels, left parts of his neck and face undried so that air might sting them and, whenever he was not saying his beads, carried his arms stiffly at his sides like a runner and never in his pockets or clasped behind him.