Reference for Bekhorot 4:57

תנא מכירה והוא הדין לקבלנות

You must, therefore, admit that when [the Mishnah] lays down that selling [to a heathen] is forbidden<span class="x" onmousemove="('comment',' The passage in the Mishnah ALTHOUGH HE IS NOT PERMITTED.');">³⁵</span>

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