Reference for Bava Metzia 38:2

מתניתין דקתני הא אמר תנו נותנין בשכיב מרע דבר מהדר הוא

Our Mishnah, which teaches [by implication] that if [the person who lost the document says,] 'Give it,' it is given, refers to [a gift made by] a dying person, who is in a position to retract.<span class="x" onmousemove="('comment',' I.e., he may yet change his mind and write a second deed, conferring the gift upon another person, and then the latter acquires it. ');">²</span>

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