Reference for Bava Batra 263:4

ואמר רבי יהודה הנחתום מעשה ואירע הדבר בבת אחותי כלה ובא מעשה לפני חכמים ואמרו תקרע כתובתה ותעמוד על מתנתה ונמצאת קרחת מכאן ומכאן

was produced against him, R. Eliezer said: She may tear up [the deed of] her gift and claim the rights of<span class="x" onmousemove="('comment',' Lit., 'and stand upon'. ');">¹²</span> her <i>kethubah</i>.<span class="x" onmousemove="('comment',' Since the gift was made later than the date of the bond of indebtedness, the creditor has the prior claim. The widow, therefore, renounces the gift, and claims her kethubah the date of which is earlier than that of the debt. She is entitled to do so according to R. Eliezer since he holds the view that she originally accepted the gift with the object of gaining any amount over and above her kethubah, but not to lose any of the rights to which that document entitled her. ');">¹³</span> But the Sages said: She tears up her <i>kethubah</i>,<span class="x" onmousemove="('comment',' by accepting her husband's gift she is assumed, according to the Sages, to have renounced the rights of her kethubah as far as that property (which formed part of the gift) is concerned. ');">¹⁴</span> remains with the claim of her gift,<span class="x" onmousemove="('comment',' Which, owing to the debt which antedated it, is invalid. ');">¹⁵</span>

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