Leviticus 13:20-22

BRG Bible

²⁰ And if, when the priest seeth it, behold, it be in sight lower than the skin, and the hair thereof be turned white; the priest shall pronounce him unclean: it is a plague of leprosy broken out of the boil.

²¹ But if the priest look on it, and, behold, there be no white hairs therein, and if it be not lower than the skin, but be somewhat dark; then the priest shall shut him up seven days:

²² And if it spread much abroad in the skin, then the priest shall pronounce him unclean: it is a plague.