Reference for Eruvin 187:4

ולשמואל למה לי הא הא אמר זה מטלטל עד עיקר מחיצה וזה מטלטל עד עיקר מחיצה

'Take a cloak', said Samuel to the people, 'and spread it across,<span class="x" onmousemove="('comment',' To form a partition at the gap, in order that the tenants of the adjoining courtyards shall not impose restrictions upon each other.');">⁶</span> and Rab turned away his face.<span class="x" onmousemove="('comment',' As a mark of his displeasure. Presumably because in his opinion the collapse of the wall, which exposed the courtyards to one another, caused also the respective tenants to impose restrictions upon each other, in consequence of which it was forbidden to move the cloak from its place to the gap.');">⁷</span>

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