Reference for Chullin 73:25

דאי ס"ד מסוכנת אסירא השתא מסוכנת דלא מחסרא אסירא טרפה מיבעיא

This cannot be, for it is written: And if any beast, of which ye may eat, die, he that touches the carcass [nebelah] thereof shall be unclean until the even,<span class="x" onmousemove="('comment',' Lev. XI, 39.');">¹¹</span>

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