Responsa על בבא קמא 72:16

Q. While critically ill, Mrs. Maimona said to the representative of the community that after her death the following matters should be attended to at her expense: 1) That the oil-lamp which burns during the services in the memory of her departed daughter, should be made to burn continuously day and night; 2) that every Friday evening a half-pound waxen candle should be lit in the synagogue in her memory; and 3) that half a mark should be expended on a kiddush-cup for the synagogue. When the representative asked her as to the source of the money for these expenditures, she answered pointing at an adjoining room: "You will find sufficient valuables and money in that room." The following day, a Friday, she called her brother Zemah and told him, in the presence of witnesses, to take for himself and for his sisters everything he finds in the room mentioned above. On the following Sunday, the representatives of the community came and asked her the whereabouts of the money she promised for the synagogue, but she refused to reveal anything. The representatives, therefore, broke into the room and took everything they found there. They also pronounced the herem against anyone who would not return to the community valuables or money belonging to Mrs. M. which might be in his possession. R. Isaac ha-Kohen admitted that Mrs. M. had deposited eight Cologne-marks with him and had told him that after her death he should do with the money "the proper thing."
A. Mrs. M. probably withdrew her promise to donate something to the synagogue. A gift made causa mortis even to a holy cause can be rescinded. The money and valuables found in her room, therefore, belong half to R. Zemah and half to his sisters. R. Isaac must return the eight marks to Mrs. M's heirs, for the proper thing to do with money of a deceased person, is to return it to the heirs.
This Resp. is addressed to R. Jacob and the community of Linpurk.
SOURCES: Pr. 998: Mord. B. B. 624; Mordecai Hagadol, p. 326d; Agudah B. B. 202. Cf. Maharil, Responsa 75; Isserlein, Pesakim 73.