Leviticus 13:27 in the World English Bible
The priest shall examine him on the seventh day. If it has spread in the skin, then the priest shall pronounce him unclean. It is the plague of leprosy.
Context
26 But if the priest look on it, and, behold, there be no white hair in the bright spot, and it be no lower than the other skin, but be somewhat dark; then the priest shall shut him up seven days:
27 And the priest shall look upon him the seventh day: and if it be spread much abroad in the skin, then the priest shall pronounce him unclean: it is the plague of leprosy.
28 And if the bright spot stay in his place, and spread not in the skin, but it be somewhat dark; it is a rising of the burning, and the priest shall pronounce him clean: for it is an inflammation of the burning.