Reference for Niddah 69:18

בשניה בודקין אותו

remains free for the purpose of including a leper in regard to his source and 'or a woman' serves to include a female leper in regard to her sources; and the All Merciful has compared<span class="x" onmousemove="('comment',' By including the expression of 'whether it be a man' (applied to the leper) in the text dealing with the zab. ');">¹⁷</span>

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