Reference for Zevachim 98:21

לאו למימרא דדבר הלמד בהיקש אין חוזר ומלמד בגזירה שוה

and [thereby] his head<span class="x" onmousemove="('comment',' I.e., the leprosy of his head, such as a scale, or karahath or gabbahath.');">³²</span> is assimilated [through a hekkesh] to his feet:<span class="x" onmousemove="('comment',' I.e., to the rest of the body.');">³³</span>

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