Reference for Niddah 110:17

דתניא

two; while after the third issue the All Merciful compared him to the 'woman',<span class="x" onmousemove="('comment',' Who becomes unclean even in a case of an accidental issue. After no more than two issues a man does not become unclean unless they were intentional. ');">¹⁶</span>

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