מדרש על ויקרא 13:12

1) "And if the leprosy blossom": What is the intent of this? (i.e., Why not merely state "if it blossomed"?) I might think that the blossoming is tahor only from a se'eth (the appearance under discussion). Whence do I derive the same for the other appearances? From "the leprosy." "and the leprosy cover": not the bohak (white scurf). For I would say that since it is a sign of cleanliness at the end (see Chapter 6:2), it is also a sign of cleanliness in the beginning; it is, therefore, written "and the leprosy cover," and not the bohak.

2) I might think that all of the inspections of the day are kasher. It is, therefore, written (Vayikra 13:12): "to all the sight of the eyes of the Cohein." Just as with the Cohein — except when the light of his eyes has dimmed, so with the day — except when the light of the day has dimmed.

2) "all the skin of the plague-spot": skin which is susceptible of a plague-spot — to exclude a "rebellious" boil or a "rebellious" burn. — But perhaps the intent (of "all the skin of the plague-spot") is (the amount of) skin that is susceptible of (the minimal size of) a plague-spot — a garis — that that (if it is not covered) can impede "all of the skin"); but that which is not susceptible of a plague-spot the size of a garis does not impede it. It is, therefore, (to negate this) written "all of it has turned white." If "all of it has turned white," I might think (even) the midst of his head (must be covered to qualify as "all of his skin"); it is, therefore, written "from his head" — to exclude the midst of his head; "until his feet" — to exclude the midst (i.e., the soles) of his feet.