Reference for Nedarim 143:6

כשלא שמע ארוס ושמע האב דבו ביום הוא דמצי מיפר אבל מכאן ואילך לא מצי מיפר

Come and hear: If she vowed on one day, and he divorced her on the same day and took her back on the same day, he cannot annul it.<span class="x" onmousemove="('comment',' Now it is assumed that it refers to mere betrothal. ');">⁵</span>

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