Reference for Niddah 111:3

דם היוצא מפי האמה מנלן דטהור

could prove the contrary, for though it issues from an unclean region it is nevertheless clean; you also need not, therefore, be surprised at this that, though it issues from an unclean region, it should be clean. Hence it was explicitly stated, 'His issue is unclean and this', to include his urine in respect of uncleanness. Whence is it deduced that the blood that issues from the orifice of the membrum<span class="x" onmousemove="('comment',' Of a confirmed zab. ');">²</span>

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