Reference for Bava Kamma 237:5

אורי ליה רב יהודה לאדא דיילא כדברי האומר אפילו מיעוט שלו

It was stated: In the case of a robber, when would it be allowed to buy<span class="x" onmousemove="('comment',' Var. lec. 'to collect a debt' or 'to derive a benefit'. ');">⁶</span> [goods] from him? — Rab said: Only when the majority [of his possessions] is his, but Samuel said: Even when only the minority [of them] is his. Rab Judah instructed Adda the attendant<span class="x" onmousemove="('comment',' Lit., 'one who pours water over another person's hands' (Jast.). ');">⁷</span>

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