Reference for Bekhorot 50:18

אלימא דבעל מום הוא ולישקליה מכלל דתנא קמא אמר לאו

one authority maintaining that we enact a prohibition as a precaution lest he should come to detain it,<span class="x" onmousemove="('comment',' So that he can avail himself of its wool from time to time and in so doing he may come to break the law regarding working and shearing it.');">¹⁰</span>

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