1) GIVING TO A PERSON AGAINST HIS WILL
QUESTION: The Gemara cites the Mishnah in Erchin (31b) which describes Hillel's enactment with regard to the law of buying back a house in a walled city. One who sells a house in a walled city may redeem his house from the buyer for up to one year after the sale (Vayikra 25:29-30). During that year, the buyer of the house must return the house to the seller should the seller offer to refund the money. If the seller does not redeem his house within the first year, the buyer may keep it and the seller loses it forever. At one point, it happened that the buyers of such houses would hide themselves near the end of the year so that the original owners would not be able to find them in order to redeem their houses. Hillel enacted that "the money may be deposited in a certain office... and thereafter the original owner may break down the door and enter the house." That is, Hillel enacted that the original owner could redeem his house against the will of the occupant.
Rava proves from Hillel's enactment that when a person gives something against the will of the recipient, it is not considered a valid "Nesinah" (act of giving). He proves this from the fact that Hillel found it necessary to make a special enactment that the original owner may put the money for the house in an office that was designated for that purpose, rather than give the money directly to the buyer against the buyer's will.
Rav Papa refutes Rava's proof by pointing out that Hillel's enactment was only necessary for when the buyer is not present (he is hiding from the original owner), as the Mishnah states. When the buyer is present, the original owner may give him the money against his will.
What was Rava's reasoning? Rav Papa's logic seems obvious! Hillel's enactment was to provide an office which would be considered the property of the buyer so that the seller could deliver money to the buyer by putting it in that office, even though the buyer is not present. When the buyer is present (or when any of his property is accessible), it would not be necessary to put the money in an office, but rather it could be given directly to the buyer against his will (or placed upon his property). Hillel's enactment did not relate to the fact that giving against the recipient's will is not considered "Nesinah." Rather, when the person is not present, it is impossible to give him anything.
ANSWERS: The Rishonim discuss this question and offer various solutions.
(a) TOSFOS in Erchin (32a, DH mid'Itztrich) and the TOSFOS HA'ROSH here explain that if giving something against the recipient's will is considered a valid "Nesinah," since the original owner may give the money to the buyer against his will he may not only give the money directly to the buyer but he may give it even to another person to acquire it on behalf of the buyer against the buyer's will. Hence, if "Nesinah" against the recipient's will is a valid "Nesinah," Hillel would not have had to designate an office into which to put the money. Since Hillel did designate such an office, it must be that the buyer cannot be paid against his will even when he is present.
(b) The RASHBA asks a strong question on the approach of Tosfos and the Tosfos ha'Rosh. The Halachah is that a Get may be given to a woman against her will when she is present, but when she is not present a Get may not be given to a third party to acquire it on behalf of the woman, because a Get is a Chov (liability) to the woman (Gitin 11b).
The Rashba therefore concludes that Rava indeed cannot prove from Hillel's enactment that giving against the recipient's will is considered an act of "Nesinah." Rather, his proof is based on the logical consideration that even when the recipient is present, giving something to him against his will is not considered a "Nesinah," just as it is not considered a "Nesinah" when he is not present.
How, though, will Tosfos answer the Rashba's question? Why may the money be given to the recipient through Zechiyah (via a third party) against his will, while a Get may not be given to a woman through Zechiyah against her will?
1. The DEVAR YAKOV suggests an answer based on the RAN (Gitin 37a). The Ran asks how a lender can be Mezakeh land to a borrower in order for his Pruzbul to be effective. Giving the land to the borrower should be considered a Chov to the borrower, since it causes the debt to remain in force! The Ran answers that perhaps when receiving something that is essentially a Zechus (benefit) to the recipient, even if it results indirectly in a loss, it is still considered a Zechus and the principle of "Zachin l'Adam she'Lo b'Fanav" applies.
The same logic may apply in our case. Since receiving money is essentially beneficial for the buyer of the house, it is considered a Zechus, even though it results in the loss of the house that he bought.
In contrast, receiving a Get is not essentially a Zechus for the woman.
2. Perhaps the Rashba and Tosfos are following their respective opinions regarding what is considered a "Nesinah" of a Get, or of money for a house against the recipient's well.
From Tosfos (end of DH Michlal), it seems that when a person gives a Get stipulating that the wife must give him 200 Zuz, he means not only that the wife should hand over to him the money, but that he should acquire the money that she gives to him. The same might be true about a house in a walled city. It is not sufficient for the original owner to hand over the money to the buyer, but rather the buyer must acquire the money. Regarding a Get, though, the opposite is true; it is necessary to hand over a Get to the wife, even if she does not acquire it (for example, where the wife is a Ketanah or a Shotah who cannot make acquisitions), and if she acquires the Get without the husband giving it to her, it is not a valid Get. Therefore, if a man tries to be Mezakeh a Get to his wife against her will, since the Mezakeh, the third party, is not a Shali'ach, it is not considered as though the Get was placed by the husband into her hands, and the Get is not valid. In contrast, in the case of a house in a walled city, if the Mezakeh acquires the money for the buyer, then the sale is revoked.
This explains why the Gemara does not learn from the verse, "v'Nasan b'Yadah" (Devarim 24:1) which teaches that a man may divorce his wife against his will, that giving something against the recipient's will is considered a valid "Nesinah" (and falls into the category of "v'Nasan"). The verse cannot prove that a person can acquire something against his will.
The Rashba, however, explains that even if giving against the recipient's will is considered a "Nesinah," it cannot enable the recipient to acquire the item. Rather, in the case of a house in a walled city, it is sufficient to place money in the property of the buyer, whether or not he acquires it. In the case of a Get, it is sufficient for the woman to place money in the husband's hand against his will, if giving against a person's will is considered a "Nesinah." Consequently, paying the buyer of the house may indeed be compared to giving the Get to a woman. The Rashba in fact asks why the Gemara does not learn from "v'Nasan b'Yadah" that a "Nesinah" against one's will is considered a "Nesinah" (see also RASHASH; the Rashba answers this question by differentiating between giving something and giving back something).
Since the Rashba compares Get Ishah to a house in a walled city, he may indeed prove from Get that one cannot be Mezakeh money through a third party to the buyer of a house in a walled city.

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