Reference for Yevamot 49:7

ולא היא התם אלומי אלמיה לקלא הכא אמרינן קם ביה בקלא וליתיה:

she was taken away;<span class="x" onmousemove="('comment',' By the Beth din acting on the evidence of witnesses. ');">²³</span> here he<span class="x" onmousemove="('comment',' Her husband at his own discretion. ');">²⁴</span> had let her go.<span class="x" onmousemove="('comment',' And the prohibition to remarry her is only Rabbinical. Hence it is possible that once he has remarried her he need not part from her. ');">²⁵</span> And Rabbah son of R. Nahman?<span class="x" onmousemove="('comment',' How can he draw a comparison between two dissimilar cases? ');">²⁶</span>

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