Leviticus 13:2-3, 44-46

When a man shall have in the skin of his flesh a rising, or a scab, or a bright spot, and it become in the skin of his flesh the plague of leprosy, then he shall be brought unto Aaron the priest, or unto one of his sons the priests: and the priest shall look on the plague in the skin of the flesh: and if the hair in the plague be turned white, and the appearance of the plague be deeper than the skin of his flesh, it is the plague of leprosy; and the priest shall look on him, and pronounce him unclean.

he is a leprous man, he is unclean: the priest shall surely pronounce him unclean; his plague is in his head. And the leper in whom the plague is, his clothes shall be rent, and the hair of his head shall go loose, and he shall cover his upper lip, and shall cry, Unclean, unclean. All the days wherein the plague is in him he shall be unclean; he is unclean: he shall dwell alone; without the camp shall his dwelling be.