The Gardnerian Book of Shadows, by Gerald Gardner, at sacred-texts.com
Learn of the spirit that goeth with burdens that have not honour, for 'tis the spirit that stoopeth the shoulders and not the weight. Armour is heavy, yet it is a proud burden and a man standeth upright in it. Limiting and constraining any of the senses serves to increase the concentration of another. Shutting the eyes aids the hearing. So the binding of the initiate's hands increases the mental perception, while the scourge increaseth the inner vision. So the initiate goeth through it proudly, like a princess, knowing it but serves to increase her glory. But this can only be done by the aid of another intelligence and in a circle, to prevent the power thus generated being lost. Priests attempt to do the same with their scourgings and mortifications of the flesh. But lacking the aid of bonds and their attention being distracted by their scourging themselves and what little power they do produce being dissipated, as they do not usually work within a circle, it is little wonder that they oft fail. Monks and hermits do better, as they are apt to work in tiny cells and coves, which in some way act as circles. The Knights of the Temple, who used mutually to scourge each other in an octagon, did better still; but they apparently did not know the virtue of bonds and did evil, man to man. But perhaps some did know? What of the Church's charge that they wore girdles or cords?