Gemara

Our Mishnah means that if he divorced her on condition that she return his garment, and she lost it, since he specifically wanted it, she cannot fulfill the Tenai. R. Shimon ben Gamliel says, it suffices to return its value. Such a case occurred in Tzidon, and Chachamim ruled that it suffices that she return its value.

Question (R. Asi): If one said 'this is your Get on condition that you give to me 200 Zuz', and then he pardoned her from paying, what is the law?

Chachamim said that she cannot fulfill the condition with money only because he didn't pardon her. Perhaps here is different, for he pardoned her! Perhaps R. Shimon allows appeases him with the money, but here she did nothing!

Answer (R. Yochanan): She is not divorced.

Question (Mishnah - R. Meir): If Reuven told Shimon 'my property is forbidden to you, unless you give to my son a Kor of wheat, he is forbidden until he gives;

Chachamim say, he can permit this by saying 'I consider it as if I received.'

Answer: Here is different, for he stipulated in order to pain his wife. There, Reuven stipulated for his own benefit. He may decide that he does not need it.

(Rav Yosef): If David told Levi 'other sharecroppers irrigate three times a year for a fourth of the yield. Irrigate four times, and I will give you a third.' Rain came, and there was no need for extra water. He did no extra work, so he gets only a fourth.

Rabah: It was not needed (he fulfilled his contract). He gets the full third.

Suggestion: Rav Yosef holds like Chachamim, and Rabah holds like R. Shimon.

Rejection: The Halachah follows Rabah, and the Halachah is unlike R. Shimon!

Conclusion: Indeed, Rav Yosef holds like Chachamim, but Rabah could hold like Chachamim. They say regarding divorce that money cannot replace the garment, for he wanted to pain her. Here, Reuven only intended that his crops be watered!

Kesuvos 72b (Mishnah): If a man was Mekadesh a woman on Tenai that she has no vows and she was found to have, she is not Mekudeshes. If he did Nisu'in Stam (without specifying) and she had vows, she leaves without a Kesuvah.

(Rav): If a man was Mekadesh a girl on Tenai and did Nisu'in with her Stam (and the Tenai was not fulfilled), she needs a Get from him;

(Shmuel): She does not need a Get.

(Abaye): Rav does not assume that since he did not mention the Tenai at the Nisu'in, he pardoned it. Rather, men avoid Bi'as Zenus (they intend for Kidushin).

(Rav Acha bar Yakov): If one made Kidushin on Tenai and had Bi'ah, all agree that a Get is not required.

74a (Rav Kahana): If one was Mekadesh on Tenai and had Bi'ah, she needs a Get. A case occurred, and Chachamim could not permit her without a Get.

This is unlike the following Tana:

(Rav Yehudah citing R. Yishmael): If "she was not grabbed" she is forbidden. Had she been grabbed, she would be permitted;

In another case she is permitted even if she was not grabbed, i.e. mistaken Kidushin. Even if she has a child, she may do Mi'un and leave him.

Rishonim

Rif and Rosh (Kesuvos 34a and 7:11): Rabah taught that Rav and Shmuel argue about a Ta'os involving one woman like the case of two women, i.e. he later had Nisu'in. A simple Ta'os involving one woman is when he was Mekadesh on Tenai and had Bi'ah (i.e. immediately), for then we cannot say that he pardoned the Tenai. However, we conclude unlike Rabah. Rav Kahana taught that if a man was Mekadesh on Tenai and had Bi'ah, she needs a Get. A case occurred, and a Get was required. The Halachah is unlike R. Yishmael, who allows Mi'un after Kidushei Ta'os, even if there was Bi'ah after maturity. Nidah 52a supports this.

Rambam (Hilchos Ishus 7:23): If a man was Mekadesh a girl on Tenai and days later he was Mevatel the Tenai, even though they were alone and he did not Mevatel it in front of witnesses, the Tenai is Batel and she is Mekudeshes Stam.

Rebuttal (Ra'avad): This is wrong, unless he had Nisu'in with witnesses, which is like Bitul of the Tenai in front of witnesses.

Ran (Kesuvos 33b) and Magid Mishneh: The Rambam and Ra'avad learn from the Hava Amina that Rav requires a Get due to Bitul ha'Tenai. Abaye rejected this, but the end of the Sugya shows that Bitul works. The Rambam infers that witnesses are not needed, for the Sugya did not mention them.

Gra (EH 38:45): Rav and Shmuel argue about whether or not we assume that he pardoned the Tenai in his heart!

Question: Bitul helps for a Tenai 'that you will pay me 200 Zuz', for one can say 'it is as if you paid me.' How does it help for non-monetary Tana'im?

Answer (Ran): Since he stipulated for his benefit, he does not want the Kidushin to be Batel immediately, until he learns about the vow or sees the blemish and is Makpid (upset). He wants the Kidushin to be valid if it does not bother him. However, once he was Makpid, he cannot Mevatel the Tenai.

Question: In Kidushin (48b), we find that one cannot Mevatel a Tenai, e.g. 'on condition that I am wealthy'!

Answer #1 (Ran): Indeed, she can say 'I consider it as if he is wealthy'. The case is, she did not say so, rather 'at the time of Kidushin I meant to accept even if he is not'. Devarim sheb'Lev do not help, so she is not Mekudeshes.

Rebuttal (Ran): If she was not Makpid from the beginning to the end, this is no worse than pardoning the Tenai! The Gemara does not connote that initially she did not care, but now she does!

Answer #2 (Ran): Since she did not care, the Tenai was not for her benefit. The above reasoning (vi) does not apply, so she cannot Mevatel the Tenai.

Ran (ibid.): Regarding a Get one cannot pardon even a Tenai for one's benefit, e.g. that you will pay me 200 Zuz, for he stipulated to pain her. The Rashba says that only for a monetary Tenai, e.g. that you will pay me 200 Zuz, one can say 'I consider it as if you paid me.' In the Hava Amina that Rav requires a Get because he was Mevatel the Tenai, i.e. and had Bi'ah l'Shem Kidushin. He pays a full Kesuvah if he divorces her, even if the Tenai was not fulfilled. Abaye teaches unlike this. Rather, he has Bi'ah l'Shem Kidushin only to avoid Bi'as Zenus, but regarding the Kesuvah he did not pardon the Tenai.

Rambam (ibid.): The same applies if she accepted Kidushin on Tenai and later she was Mevatel the Tenai when they were alone.

Rosh (ibid.): Rashi and Tosfos connote that because a person does not have Bi'as Zenus, he Vadai intends for Kidushei Bi'ah. There must be witnesses of seclusion. They are considered to be witnesses of Bi'ah.

Gra (EH 38:44 DH Likut): Rashi and the Rosh hold that he cannot pardon the Tenai. Rather, he has Bi'ah l'Shem Kidushin; it must be in front of witnesses.

Poskim

Shulchan Aruch (EH 38:35): If one was Mekadesh a girl on Tenai and days later he was Mevatel the Tenai, even between them without witnesses, the Tenai is Batel and she is Mekudeshes Stam. The same applies if she accepted Kidushin on Tenai and later she was Mevatel the Tenai when they were alone.

Bach (DH Chosav ha'Rambam): If he says that he was Mevatel the Tenai and she denies this, letter of the law he is not believed, for he would have done so in front of witnesses. However, l'Ma'aseh she is Safek Mekudeshes.

Rebuttal (Chelkas Mechokek 47): This is like any case when he says that he was Mekadesh her and she denies it. He is forbidden to her relatives and she is permitted to his (Kidushin 65a), for ha'Motzi mi'Chavero Alav ha'Re'ayah.

Beis Shmuel (57,58): He can Mevatel even a Tenai not of money, and the Kidushin takes effect retroactively, since the Tenai was for his benefit. Since the original Kidushin was in front of witnesses, the Bitul need not be. The Kidushin is Batel only if he is Makpid when he finds out (e.g. about vows). If he was Makpid when he found out, he cannot pardon the Tenai later. Perhaps regarding a monetary Tenai he can, for this is as if it was fulfilled.