Reference for Bava Kamma 80:7

משום דא"ל כי היכא דמשתעבדנא לדידך הכי נמי משתעבדנא להאיך מדר' נתן

This indeed could be effectively argued [by the borrower] where the owner possessed property, but what could be argued in the case where the owner possessed no property? — What therefore the borrower could always argue against the owner is [as follows]: 'Just as I am under a personal obligation to you,<span class="x" onmousemove="('comment',' To return the ox. ');">⁷</span>

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