Reference for Niddah 67:1

רגל הוה וטומאת עם הארץ ברגל כטהרה שוינהו רבנן דכתיב

The incident occurred during a festival and the uncleanness of an 'am ha-arez<span class="x" onmousemove="('comment',' Who was no Sadducee and whose wife as a rule properly observed the laws of menstruation. ');">¹</span>

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