Leviticus 13:1-2, 44-46

1 Yahweh said to Moses and Aaron,

2 'If a swelling or scab or spot appears on someone's skin, which could develop into a contagious skin-disease, that person must then be taken to the priest, either Aaron or one of his sons.

44 the person has such a disease: he is unclean. The priest will declare him unclean; he has a contagious skin-disease of the head.

45 'Anyone with a contagious skin-disease will wear torn clothing and disordered hair; and will cover the upper lip and shout, "Unclean, unclean."

46 As long as the disease lasts, such a person will be unclean and, being unclean, will live alone and live outside the camp.