Reference for Bekhorot 58:2

בית הפרס שנידש טהור

Or, we may also say: [The Mishnah refers] to other impurities,<span class="x" onmousemove="('comment',' E.g., coming in contact with a carcass or dead reptile, the negative precept cited above referring exclusively to a corpse.');">²</span>

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