Midrash su Levitico 13:22

6) This tells me only of a boil which arose of itself. Whence do I derive for inclusion as a boil the result of a blow from a stick, a stone, or peat, (or the result of bathing in) the hot springs of Tiberias, or of anything which is not caused by fire? From "boil" and again [Vayikra 13:19]) "boil," implying extension of inclusion. This tells me only of a boil (which arose) after the pronouncement. Whence do I derive the same for (a boil which arose) before the pronouncement? (This tells me only of a boil which arose) in a proselyte after he converted. Whence do I derive the same for (a boil which arose in a proselyte) before he converted? Of (a boil which arose) in a minor after he was born. Whence do I derive the same for (a boil which arose) in a minor before he was born? From "boil," "boil," for extension of inclusion. This tells me only of a boil which has room to spread, (it being written afterwards [Vayikra 13:22] "And if it spread in the skin"). Whence to I derive the same for a boil which does not have room to spread? From "if there be in it" — even in all of it. This tells me only (of an instance of) part-boil, part-bahereth; part-bahereth, all boil. Whence do I derive the same for part-boil, all bahereth? From "if there be in it" — even in all of it. "in its skin" — even in all of it (i.e., all boil-all bahereth).

6) (Vayikra 13:22) ("And if it spreads, spreads, in the skin, the Cohein shall declare him tamei; it is plague.") "spreads, spreads, in the skin": What is the intent of this? Because it is written (Vayikra 13:27) "And the Cohein shall see him on the seventh day, if it spreads, spreads, in the skin," I might think that a spreading renders him unclean only on the seventh day. Whence do I derive the same for the eighth, ninth, and tenth day? From (the redundant) "spread, spread."

7) If he were confirmed through white hair, and the white hair disappeared and then returned; and, similarly, through a spreading: at first inspection, at the end of a week, after exemption — where he was confirmed through the spreading and the spreading disappeared and then returned — and similarly, through white hair, at the end of the first or the second week, or after exemption — in respect to all of these instances, it is written (the redundant) "and if it spreads, spreads."