Retraction #1 (of 3:b, Daf 4b): Rather, Shmuel taught that Reuven (who vowed from Shimon) is forbidden and Shimon is permitted only if Reuven said 'that I will eat (or taste) from you.' If he said only 'I am Mudar from you', both of them are forbidden.

This is like R. Yosi b'Rebbi Chanina taught:

(R. Yosi b'Rebbi Chanina): If Reuven told Shimon "I am Mudar from you," both of them are forbidden.

Question (Mishnah): If Reuven told Shimon "I am Cherem to you", Shimon is forbidden.

Reuven is permitted (even though he did not say 'that I will eat (or taste) from you')!

Answer: The case is, he explicitly said 'you are not forbidden to me.'

Question (Mishnah): If Reuven told Shimon "you are Cherem to me", Reuven is forbidden.

Shimon is permitted!

Answer: The case is, he explicitly said 'I am not forbidden to you.'

Inference: Stam (without specifying), both of them are forbidden.

Objection (Seifa): If he said 'I am (Cherem) to you and you are to me', both of them are forbidden.

Inference: Stam (if he did not add 'you are forbidden to me'), Reuven is forbidden to Shimon, but not vice-versa!

Retraction: R. Yosi b'Rebbi Chanina taught that if Reuven said "I am Mudar to you," both of them are forbidden. If he said "I am Mudar from you," he is forbidden and Shimon is permitted.

Question: In our Mishnah, he said "I am Mudar from you", yet Shmuel taught that only if he said 'that I will eat (or taste) from you', Reuven is forbidden and Shimon is permitted. If he said only 'I am Mudar from you', both of them are forbidden!

Retraction #2 (of 3:b): Rather, Shmuel taught that Reuven is forbidden to eat from Shimon but may get other benefit from him only if Reuven said 'that I will eat (or taste) from you.' If he said only 'I am Mudar from you', he may not benefit from him at all.

Rejection: If so, Shmuel should have said 'if he did not say 'that I will eat (or taste) from you', even benefit is forbidden!' (This is the Rishonim's text.)

Retraction #3: Rather, Shmuel taught that Reuven is forbidden only if he said also 'that I will eat (or taste) from you.' If he said only 'I am Mudar from you', this does not connote that he forbids himself.

Question: What is the reason?

Answer: Perhaps he did not intend to forbid benefit;

'I am Mudar from you' could mean that he will not speak with him. 'I am separated from you' could mean that he will not do business with him. 'I am distanced from you' could mean that he will not stand within four Amos of him. (Some say that these matters are forbidden. Some permit them, for perhaps he does not forbid them, rather, getting benefit!)

Suggestion: This shows that Shmuel holds that ambiguous Yados are invalid.

Answer: Indeed, he establishes the Mishnah like R. Yehudah, who says that ambiguous Yados are invalid:

(Mishnah): The essential part of a Get is 'you are permitted to every man';

R. Yehudah adds 'and this will be for you, from me, a Sefer of cutting, a letter of abandonment...' (he must specify that he divorces her through this Get).

Question: Why does Shmuel establish the Mishnah to be like R. Yehudah (and he also said 'that I will eat from you')? He could establish it simply, like Chachamim, who say that ambiguous Yados are valid!

Answer (Rava): Shmuel found the Mishnah to be difficult. Why does it say 'that I will eat (or taste) Lecha? We must say that we need 'Lecha', for Yados must be clear.

(Abaye): Ambiguous Yados are valid.

(Rava): They are invalid.

(Rava citing R. Idi): "Nazir Lehazir" teaches that Yados for Nezirus must be like Nezirus, i.e. unambiguous.

Suggestion: Abaye and Rava argue like Chachamim and R. Yehudah:

(Mishnah): The essential part of a Get is 'You are permitted to every man';

R. Yehudah says, it is 'and this will be for you, from me, a Sefer of cutting...'

Abaye holds like Chachamim, and Rava holds like R. Yehudah!

Rejection #1: Even R. Yehudah could agree with Abaye. R. Yehudah requires unambiguous Yados only for a Get, which requires Kerisus (a total severance).

Rejection #2: Even Chachamim could agree with Rava. Chachamim allow ambiguous Yados only for a Get, for one cannot divorce another man's wife (so it is clear that he divorces her). We have no source to allow ambiguous Yados in other cases.