Reference for Chullin 256:19

אמר רב יהודה אמר רב

And where is there proof in Scripture that a limb torn away from a living animal renders unclean? - Rab Judah said in the name of Rab: It is written: And if there die of the beasts.<span class="x" onmousemove="('comment',' Lev. XI, 39. The exposition is inferred from the Heb. , 'of the beasts', i.e., a part thereof. Thus a limb that has died (i.e., torn away from the beast) renders unclean. vnvcv in');">¹¹</span>

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