Reference for Bava Batra 304:2

כי קם אמר רב נחמן בר יצחק לרבא מאי אחוי לך אמר ליה במיפה את כחו

When he rose, R. Nahman b. Isaac asked Raba, 'What did he indicate to you?' [Raba] replied to him,' That Rab Judah's report refers to the case] where [the testator] strengthened the donee's claims.'<span class="x" onmousemove="('comment',' Lit., 'his power'. In such a case the donee acquires possession after death even where the testator ordered the writing of a deed. ');">⁵</span> In what manner [is it indicated that one wished to] strengthen the donee's claims? — R. Hisda replied: [By including in the deed the formula]. 'And we<span class="x" onmousemove="('comment',' I.e., 'witnesses'. ');">⁶</span> acquired from him<span class="x" onmousemove="('comment',' I.e., from the testator on behalf of the donee, by means of symbolic acquisition. ');">⁷</span> in addition to this [presentation of the] gift.'<span class="x" onmousemove="('comment',' Supra 136a. ');">⁸</span>

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