1) CONSENT TO WRITE A "SHTAR"
QUESTION: The Gemara teaches that when a person sells a field and tells a Shali'ach to make a Kinyan on the field on behalf of the buyer and to write a Shtar, with witnesses, for the purchase, the seller may not retract from the sale because the Shali'ach already made the Kinyan. However, he may retract from his command to write a Shtar. He may tell the Shali'ach not to deliver the Shtar as long as the Shtar has not yet reached the hands of the buyer.
How can the seller prohibit the buyer from writing a Shtar with the signatures of witnesses to attest to the sale? If the witnesses saw the sale take place, then they should be able to testify to that effect and sign a Shtar without the consent of the seller! This seems clear from the Gemara later in Bava Basra (171a) which teaches that if a buyer loses a Shtar, he may tell the witnesses to write him another Shtar without the consent of the seller, as long as the Shtar does not involve a Shibud of the property of the seller. Here, too, the witnesses should be permitted to write a Shtar that does not include Achrayus Nechasim.
TOSFOS points out that the Gemara here does not mean that the Shtar may be written but Achrayus cannot be included in the Shtar when the seller retracts his consent to write the Shtar, because the Shtar is not needed to create a Chiyuv of Achrayus in this case. The Gemara (41b) teaches that when one sells a field in front of witnesses, the Chiyuv of Achrayus is created automatically. Hence, the Shtar is necessary only as proof of the sale, and as such it should be permitted to write the Shtar even without the consent of the seller. (TOSFOS DH Chozer)
(a) The PISKEI RID and the RA'AVAD cited by the Shitah Mekubetzes explain that the Gemara indeed prohibits the writing of the Shtar without the permission of the seller only when the Shtar includes Achrayus Nechasim. For example, if the seller specified at the time of the sale that he does not want to obligate himself with a Chiyuv of Achrayus unless he later writes a Shtar to obligate himself, the seller may change his mind about writing that Shtar.
How can these Rishonim say that the Gemara is discussing such a limited and specific case, when the Gemara makes no mention of such specific circumstances? These Rishonim explain that the Gemara (on 41b) does not mean that every sale without a Shtar includes a Chiyuv of Achrayus. Rather, the Gemara means that if the seller specifies that he is obligating himself with Achrayus, then the buyer may collect not only from Nechasim Bnei Chorin, but even from Nechasim Meshubadim. They infer this from the Gemara in Bava Metzia (14a) which says that "Achrayus Ta'us Sofer," which means that (according to the Rabanan who argue with Rebbi Meir) when a Shtar written for a sale does not specify a Chiyuv of Achrayus, it is assumed that there is a Chiyuv of Achrayus anyway and that the scribe merely forget to write it in the Shtar. These words imply that only with a written Shtar is it assumed that the seller intended to obligate himself with Achrayus even if it is not written in the Shtar, since he went through the trouble of writing a Shtar. In contrast, when the field is sold without a Shtar, it is assumed that the seller is not Chayav for Achrayus unless he explicitly says that he accepts Achrayus.
(b) RABEINU YEHONASAN cited by the Shitah Mekubetzes writes that the Shtar may be written even without the seller's permission. When the Gemara says that the seller may change his mind, it means that if he originally offered to pay for the writing of the Shtar, he may change his mind and the buyer will have to pay on his own to have the Shtar written.
(c) TOSFOS answers that a Shtar that was lost may be rewritten since the seller has nothing to lose if the Shtar is rewritten. In the case of the Gemara here, however, the seller will lose if a Shtar is written, because there never was a Shtar until now. A Shtar publicizes that the person has sold his land, and thus people will not want to extend loans to him since he does not have as much real estate to collateralize for the loan. The RASHBA adds that the value of his real estate will decrease when the word spreads that he needs to sell his property. (Although when one sells his property without a Shtar, his property becomes Meshubad because of the rumor (Kol), nevertheless a Shtar publicizes this even more (Rashba).)
RABEINU TAM cited by Tosfos suggests a similar answer. The Gemara here is discussing land that was given as a gift without a Shibud on the giver's Nechasim. If the recipient writes a Shtar, those who hear about the Shtar might mistakenly assume that the Shtar was either a Shtar Mecher (a bill of sale) or a Shtar Chov (a bill of debt, in which the land mentioned in the Shtar was collateral for the debt), and that the owner was Meshabed himself. Since it is to the detriment of the giver to have a Shtar written, it may not be written without his consent. (In the case in which a person lost the original Shtar, the giver does not lose by having another Shtar written, because people will realize that both Shtaros were written for the same field and it will not look like he is giving an additional field, or that he is giving a Shtar Chov.)
(d) RABEINU YONAH explains that even though there already exists a Shibud, the witnesses may not sign a Shtar which can also be used to prove that there is a Shibud without the consent of the seller, since this Shtar might be used in court to prove the Shibud. A Shtar written without the consent of the seller is not valid to prove the Shibud, since testimony must be given in front of the court and in front of the seller whom the Shibud obligates. Therefore, if the witnesses sign a Shtar without the consent of the seller, the Shtar is entirely invalid, even as proof to the transaction, since the witnesses were presenting testimony (not in the presence of the seller) that would obligate the seller to pay as a result of the Shibud.
The Gemara that allows a Shtar that was lost to be rewritten without the consent of the seller only allows the Shtar to be written without Achrayus. Such a Shtar -- which pertains only to what already happened (i.e. the field was already sold or given), but which does not obligate the seller in any future obligations (such as a Shibud) -- may be written even when not in the presence of the seller. In the case of the Gemara here, the buyer would be permitted to write a Shtar which does not include Achrayus, without the consent of the seller.
(e) The RAMBAN, RASHBA, and RAN go a step further than Rabeinu Yonah. They write that even a Shtar Ra'ayah (a Shtar used only as proof), which does not involve Achrayus, cannot be written without the consent of the seller. The reason for this is that the Torah teaches that written evidence is not accepted in court ("mi'Pihem v'Lo mi'Pi Kesavam," Kesuvos 20a). Indeed, for this reason no Shtar should be valid as proof in court. However, when the person whom the Shtar obligates requests that a Shtar be written and signed by witnesses, the signed Shtar serves as a form of Hoda'as Ba'al Din in court. The signatures simply confirm that the person admitted to his obligation by requesting that the Shtar be written. Accordingly, when the seller does not request that a Shtar be written, any testimony in the Shtar is not valid because of the rule of "mi'Pihem v'Lo mi'Pi Kesavam."
The Gemara later (171a) allows witnesses to rewrite a Shtar that was lost because the witnesses are able to testify that they were asked by the seller (or giver) to sign on a Shtar. In the case here, in which the giver tells the witnesses not to sign on a Shtar, their signatures on the Shtar are not valid testimony.
TOSFOS (39b, DH Macha'ah) presents the same approach to explain the validity of a Shtar. Why, then, does Tosfos here allow a Shtar to be written without the consent of the seller, if the seller suffers no harm from it? Perhaps it is because in the case of the Gemara here, the seller allowed the Shtar to be written at the time the buyer acquired the field. The Gemara (40a) teaches that a Kinyan made in front of witnesses is meant to be written down in a Shtar ("Stam Kinyan l'Kesivah Omed"), and the giver does not need to request from witnesses to write it down, as the Rashbam here cites. Since the Kinyan was already made with the seller's permission to commit it to writing, the seller may no longer retract his permission.
Although the Rashbam disagrees with this and writes that a Kinyan includes only implied consent, but if the seller later specifies that he does not consent to having a Shtar written he may retract his original implied consent, the RAMBAN (in Kidushin 27a) writes that the Gemara means to say more than this. The Gemara means to say that a Kinyan gives the buyer permission to write the Shtar, and the seller cannot change his mind once the Kinyan was already made. That is why Tosfos maintains that in the case of the Gemara here, it would have been permitted to write the Shtar even after the seller's retraction of his consent if not for the fact that the Shtar could harm the seller, and therefore the Kinyan -- from the start -- was not meant to be committed to writing.
2) ACQUIRING A "SHTAR" WITH "MILI"
QUESTION: The Gemara proves that it is possible to transfer the ownership of a Shtar with "Mili," words, from the ruling of Rav Huna who says that in the case of a landowner who wrote a Shtar for a sale before the sale took place, when the buyer later acquires the field he acquires the Shtar as well, even though it was not yet handed over to him. From this ruling, the Gemara attempts to prove that it is not necessary to make a strong act of Kinyan on a Shtar. Even a weak act of Kinyan (what the Gemara calls "Mili") also suffices.
The Rishonim (see TOSFOS DH Nikneh) ask how can the Gemara compare the transfer of ownership of a Shtar Mecher (a bill of sale) with the transfer of ownership of a Shtar Chov (a bill of debt)? When one transfers the ownership of a Shtar Chov, the buyer must acquire not only the proof that is written on the paper, but the debt (the Shibud) itself as well. Since the Shibud is not a tangible object, a stronger Kinyan must be made on the Shtar. The case which the Gemara is discussing, in contrast, is that of a bill of sale, where no Shibud is transferred, but where the Shtar merely testifies that a sale occurred, and therefore it does not require a strong Kinyan!
(a) TOSFOS answers that the Gemara is discussing even a Shtar Mecher that does create a Shibud, such as when the property was originally sold with a stipulation that there is no Shibud on the seller's property, and now a Shtar has been written which creates a Shibud.
Alternatively, the Shtar has new conditions in it that obligate the seller, conditions which he was not obligated to fulfill until now. (RAN)
(b) The RAN suggests further that even if the Shtar does not obligate the seller in any new obligations, it still requires a strong Kinyan, because it is not merely the paper and signatures that are being transferred; the permission of the seller to use the Shtar as proof of purchase is also being transferred. The reason for this is, as mentioned above, that testimony that is written is not valid in court (because of "mi'Pihem v'Lo mi'Pi Kesavam"). The Shtar becomes valid only because of the permission given to write it by the one whom the Shtar obligates (which makes the Shtar like Hoda'as Ba'al Din).
The Ran maintains that it does not suffice to have the permission at the time that the Shtar is written; permission must be given at the time that the Shtar is handed to the bearer (the one who will use it as proof). Therefore, a strong Kinyan is required to transfer the Shtar in order to show that the permission of the giver was given along with the Shtar. The paper alone will not suffice.