Leviticus 13:4-5

⁴If the bright spot in his skin is white, and the appearance of it is no deeper than the skin, and if the hair in the diseased area has not turned white, then the priest must isolate the one with the disease for seven days.

⁵On the seventh day, the priest must examine him to see if in his opinion the disease is not any worse, and if it has not spread in the skin. If it has not, then the priest must isolate him seven days more.