Reference for Shabbat 283:13

רבי יהודה כר' אליעזר סבירא ליה דאמר תרומה בעינא מחתא

What compels R. Hisda to interpret our Mishnah as meaning that it is required for itself?<span class="x" onmousemove="('comment',' So that he has to explain the Mishnah as referring to when the unclean terumah is on top. ');">¹³</span>

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