Reference for Chullin 258:11

אמר ליה

But perhaps the reason for R'Simeon's view there is that given by Rabbah<span class="x" onmousemove="('comment',' V. supra 127b, where Rabbah suggested as the reason for R. Simeon's view the principle that the animal cannot serve as a handle to a limb. In some texts the reading is Raba, and his explanation of R. Simeon's view is that in no circumstances can a handle serve as the means of rendering the rest susceptible to uncleanness (cf. supra 128a) .');">⁷</span>

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