Reference for Eruvin 70:9

לא קשיא הא דידיה הא דרביה דיקא נמי דקתני בזו אמר רבי דוסתאי בר ינאי משום רבי מאיר שמעתי שמקדרין בהרים ש"מ

- R'Meir is of the opinion [that the laws of the Sabbath] limits<span class="x" onmousemove="('comment',' Of which our Mishnah speaks.');">¹⁷</span> are Pentateuchal.<span class="x" onmousemove="('comment',' In a Pentateuchally doubtful prohibition the more restrictive ruling is followed. Hence R. Meir's ruling here. In the case of uncleanness, spoken of in the quoted Mishnahs, since it is only Rabbinical, the less restrictive ruling is adopted.');">¹⁸</span>

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