Reference for Moed Katan 20:1

אבל חמרא דריחיא לא

but not those of the ass turning the mill.<span class="x" onmousemove="('comment',' As not being so urgent.');">¹</span> Rab Judah<span class="x" onmousemove="('comment',' Of Pumbeditha, Rab's disciple.');">²</span>

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