Leviticus 13:4-5, 23

“But if the affected area of the skin is only a white discoloration and does not appear to be more than skin-deep, and if the hair on the spot has not turned white, the priest will quarantine the person for seven days. On the seventh day the priest will make another examination. If he finds the affected area has not changed and the problem has not spread on the skin, the priest will quarantine the person for seven more days.

But if the area grows no larger and does not spread, it is merely the scar from the boil, and the priest will pronounce the person ceremonially clean.