Leviticus 13:20-23

²⁰And if the priest see, and, behold, its appearance be lower than the skin, and the hair thereof have been turned white: then shall the priest pronounce him unclean, it is the plague of leprosy broken out in the inflammation.

²¹But if the priest see it, and, behold, there be no white hair therein, and if it be not lower than the skin, and it be pale: then shall the priest shut him up seven days.

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

²³But if the bright spot remain in its place, and spread not, it is a scar of the inflammation; and the priest shall pronounce him clean.