Leviticus 13:18-23

18"If there is in the skin of one's body a boil and it heals,

19and in the place of the boil there comes a white swelling or a reddish-white spot, then it shall be shown to the priest.

20And the priest shall look, and if it appears deeper than the skin and its hair has turned white, then the priest shall pronounce him unclean. It is a case of leprous disease that has broken out in the boil.

21But if the priest examines it and there is no white hair in it and it is not deeper than the skin, but has faded, then the priest shall shut him up seven days.

22And if it spreads in the skin, then the priest shall pronounce him unclean; it is a disease.

23But if the spot remains in one place and does not spread, it is the scar of the boil, and the priest shall pronounce him clean.