Reference for Nedarim 91:7

ת"ש היה אחד מהן מודר הנאה מחבירו ופליגי רבנן תני נדור מחבירו הנאה

TO BENEFIT FROM THE OTHER&nbsp;… and the Rabbis dispute it! — Learn, forbade himself from his neighbour.<span class="x" onmousemove="('comment',' Nadur, passive Kal. implies self-imposed. No emendation is really made in the Mishnah, but the Talmud answers that muddar may be synonymous with nadur, self-imposed. ');">⁶</span>

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