Reference for Bekhorot 68:3

לכשיולד לו נגע אחר יטהר הימנו

R'Eliezer says When another plague spot appears on him [from which he is pronounced clean], then he is cleansed from [the first].<span class="x" onmousemove="('comment',' For this proves that the first leprous spot would also have healed had it not been cut off.');">¹</span>

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