Reference for Nedarim 30:4

הלכה אסורה לא הלכה לא

An objection is raised: [If he says,] 'This loaf [of bread be forbidden] to me to-day, if I go to such and such a place to-morrow: if he eats it, he is liable to an injunction, 'he shall not go'!<span class="x" onmousemove="('comment',' This too refutes Rab Judah, since he may eat the loaf on the first day. ');">²</span>

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