Reference for Niddah 17:4

רב פפא אמר

which only involves a Rabbinical enactment.<span class="x" onmousemove="('comment',' And could, therefore, be relaxed even in the case of a pregnancy that ended in a miscarriage. As regards the pentateuchal uncleanness of a zabah, however, a miscarriage of the nature spoken of in the last cited Baraitha cannot be regarded as a proper birth. ');">⁴</span>

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