Reference for Nedarim 30:2

כי קתני דאי איתהני הרי זה בבל יחל דברו

We learnt: [If one says to his wife, 'Konam be] that which you benefit from me until the Festival, if you go to your father's house before Passover': if she goes before Passover, she may not benefit from him until the Festival, but is permitted to go after Passover. [Thus,] if she goes, she is forbidden, but not otherwise?<span class="x" onmousemove="('comment',' Though by going any time before Passover, subsequent to having benefited from her husband, the vow is violated. This contradicts Rab Judah. ');">¹</span>

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