It is upon the cleanliness of the body that sensitiveness depends; therefore people who have no regard to the cleanliness of the body are less sensitive than those who have regard to it. Besides the cleanliness of the outer part of the body, it is equally important, perhaps more important, to consider the cleanliness of the inner part of the body. Mystics, therefore, take precaution about what they eat and drink, and have methods of cleansing the inner part of the body also.