If a man or woman have a plague upon the head or the beard; Then the priest shall see the plague, and, behold, if it be in sight deeper than the skin, and there be in it yellow thin hair; then the priest shall pronounce him unclean: it is a dry scall; a leprosy upon the head or the beard.

And if the priest look on the plague of the scall, and behold, it is not in sight deeper than the skin, and that there is no black hair in it, then the priest shall shut up him that has the plague of the scall seven days:

And in the seventh day the priest shall look on the plague: and behold, if the scall spreads not, and there be in it no yellow hair, and the scall be not in sight deeper than the skin; He shall be shaven, but the scall shall he not shave; and the priest shall shut him up that hath the scall seven days more:

And in the seventh day the priest shall look on the scall: and, behold, if the scall be not spread in the skin, nor be in sight deeper than the skin, then the priest shall pronounce him clean: and he shall wash his clothes, and be clean.

But if the scall spread much in the skin after his cleansing; Then the priest shall look on him: and behold, if the scall be spread in the skin, the priest shall not seek for yellow hair; he is unclean.

But if the scall be in his sight at a stay, and there is black hair grown up therein; the scall is healed, he is clean: and the priest shall pronounce him clean.

Leviticus 13:29-37