Suggestion: Tana'im argue like Rav and R. Yochanan argue.

(Beraisa - R. Shimon ben Gamliel): If Reuven lent Shimon and he took a security at the time of the loan, and Shemitah came, even if the security is worth only half the loan, the loan is not cancelled;

Rebbi says, the loan is not cancelled only if the security is worth the entire loan.

Question: R. Shimon said 'it is not cancelled.' What does this mean?

Suggestion: The value of the security is not cancelled.

Rejection: If so, Rebbi holds that even this is cancelled. If so, why did he take a security?!

Answer: Rather, R. Shimon says that the entire loan is not cancelled, and Rebbi says that the value of the loan above the security is cancelled.

R. Shimon holds that a security acquires fully, and Rebbi holds that it only acquires according to its value.

Rejection: Really, R. Shimon means that the value of the security is not cancelled.

Question: If so, Rebbi holds that even this is cancelled. Why did he take a security?!

Answer: It is a commemoration of the loan.

Rav Kahana received partial payment for flax; the price went up.

Rav: You must give flax according to the money you received. The agreement to sell the rest is mere words. One who retracts is not considered unfaithful.

(Rav): One who retracts from an oral agreement is not considered unfaithful;

(R. Yochanan): He is considered unfaithful.

Question (Beraisa - R. Yosi b'Rebbi Yehudah) Question: Why did the Torah need to write "Hin Tzedek"? (Hin and Eifah are measures of volume. One's measures must be accurate, lest he use them to swindle when buying or selling.) It already says "Eifah Tzedek"!

Answer (R. Yosi): This teaches that your 'Hen' and 'Lav' (when you say yes or no) must be just.

Answer (Abaye): R. Yosi forbids saying something that he does not intend to fulfill. (However, one who intended to fulfill his word need not do so if circumstances (e.g. prices) change.)

Question (Beraisa - R. Shimon): Chachamim said that a garment acquires a Dinar and a Dinar does not acquire a garment, and they do not force the seller to give it. However, they said 'He who punished the generations of the flood and the dispersion, the people of Sodom and Amora and the Mitzriyim at the sea, He will punish one who does not honor his word.'

Answer: Tana'im argue about whether or not one must keep his word.

(Mishnah): A case occurred in which R. Yochanan ben Masya told his son to hire workers. His son promised to feed them.

R. Yochanan: They descend from Avraham, Yitzchak and Yakov. Even if you give them a banquet like Shlomo used to make, this does not suffice! Before they start working, tell them that you promise them only bread and beans.

If one who retracts is considered unfaithful, how could he tell his son to retract?

Rejection: That case is different. The workers themselves did not rely on the promise.

Question: What is the reason?

Answer: They knew that the son did not promise to feed them himself, rather he relied on his father.

Question: If so, why did he need to retract before they started?

Answer: The workers would assume that the father heard his son's promise and agreed to fulfill it.

Question: Did R. Yochanan really say that one who retracts from an oral agreement is considered unfaithful?

Contradiction (Rabah bar bar Chanah citing R. Yochanan): If Reuven promised to give a gift to Shimon, he can retract.

Objection: This is obvious!

Correction: Rather, he is fully permitted to retract.

Answer (Rav Papa): R. Yochanan (permits retracting only from a large gift, for Shimon is not confident of receiving it. He) forbids retracting from a promise for a small gift.

Support: R. Avahu cited R. Yochanan to say that if a Yisrael (Reuven) told a Levi (Moshe) 'I have a Kor of Ma'aser for you', Moshe may make it Terumas Ma'aser on other Ma'aser. (This is like a small gift, for Reuven owns only the right to give the Ma'aser to the Levi of his choice.)

This is reasonable if Reuven may not retract. But if he may retract, perhaps he retracted, and the Terumas Ma'aser is invalid, and Moshe will eat Ma'aser that is Tevel!

Rejection: The case is, Moshe took the Ma'aser, and deposited it back with Reuven.

Objection: R. Avahu's teaching continues 'if Reuven gave it to a different Levi, Moshe only has complaints against Reuven.' If Moshe took it, it is his!

Conclusion: This is a proper support. Reuven may not retract.

A case occurred in which Reuven gave Shimon money for sesame, and the price went up. Shimon retracted and said 'I don't have sesame. Take your money back.' Reuven did not take his money; it was stolen.

Rava: Once he told you to take your money (and you left it with him), he is not a Shomer Sachar, so he is exempt. Further, he is not even a Shomer Chinam (he would be exempt even for negligence)!

Rabanan: Shimon must accept the curse 'He who punished...'!

Rava: Indeed, if he will not give the sesame, he must accept it.

Rav Papi citing Rav Tavos: I was the seller in that story, but it was not like reported. I would not retract my word for all the money in the world!

Rather, Reuven came to me just before Shabbos, and asking to buy sesame. I refused. He asked to deposit his money with me, for Shabbos was coming. I said 'you can put it anywhere in my house that you want.' He put it in the house, and it was stolen.

Rava ruled that not only I was not a Shomer Sachar, rather, I was not even a Shomer Chinam!

Question: Rabanan said that 'he must accept the curse!'

Answer (Rav Tavos): They said no such thing.

(Mishnah - R. Shimon): Whoever is holding the money has the upper hand.

(Beraisa - R. Shimon): This is when the seller has the money and the Peros. If the seller has the money and the buyer has the Peros, he (the seller) cannot retract because his money is in his (the buyer's) hand.

Question: What does this mean? The money is in the seller's hand!

Answer: It means 'he cannot retract because what is in exchange for his money (i.e. the Peros) is in the buyer's hand.'

Objection: Obviously, he cannot retract! (Meshichah was done!)

Answer (Rava): The case is, the seller was renting the buyer's attic (where the Peros were. Rashi - therefore, the buyer did not acquire through his premises.)

Chachamim enacted that Meshichah acquires (and not money), lest someone sell something in his attic, a fire will erupt, and he will not strive to save it;

Here, the Peros are in the buyer's attic. If there is a fire, the buyer will strive to save them (so there is no need for the enactment)!

A case occurred in which Reuven paid money for wine. He heard that a powerful official of the king was marrying off a child. (Surely, he would confiscate people's wine for this.) Reuven retracted.

Rav Chisda: Just like Meshichah was enacted for sellers (that they can retract until Meshichah is done), also for buyers.

(Mishnah): (The threshold of) Ona'ah (the amount one must overpay to be able to force the seller to return the overcharge) is four Ma'os (one Ma'ah is a sixth of a Dinar) out of 24 Ma'os (a Sela), a sixth of the purchase;

(The buyer) can demand (return of the overcharge) until the time needed to show what he bought to a merchant or relative (who would tell him that he overpaid. If he delayed longer than this, he pardoned the Ona'ah.)

R. Tarfon ruled in Lud that (the threshold of) Ona'ah is eight Ma'os, i.e. a third of the purchase. The merchants rejoiced.

He told them that one may claim the Ona'ah the entire day. They reverted to conduct like Chachamim (regarding both the threshold of Ona'ah and the time to claim it).

(Gemara - Rav): The Mishnah refers to a sixth of the value of the item sold;

(Shmuel): It also refers to a sixth of the money paid.

If the value was six, and it was sold for five or seven, all agree that (the law of) Ona'ah applies (the overcharge or undercharge must be returned). They argue when he paid six and it was worth five or seven.

Shmuel holds that since the overcharge or undercharge is a sixth of the price, Ona'ah applies;

Rav holds that we always calculate based on the value of the item. If he paid six and it was worth five, (the overcharge is more than a sixth), so the sale is void. If he paid six and it was worth seven (he underpaid less than a sixth), so the undercharge is pardoned.

Shmuel says, the sale is void or the Ona'ah is pardoned only when it is not a sixth from either perspective.

Question (against Rav - Mishnah): Ona'ah is four Ma'os out of 24, a sixth of the purchase;

Suggestion: He paid 24 for something worth 20. Ona'ah also applies to an overcharge that is a sixth of the price!

Answer #1: No, he paid 20 for something worth 24.

Objection: If so, the seller was underpaid. The Mishnah continues 'he told them that the Ona'ah can be claimed the entire day';

(Rav Nachman): This only refers to the buyer, but the seller can always claim the Ona'ah.

Answer #2: Rather, he paid 28 and it was worth 24.

Support (for Shmuel - Beraisa): Whoever was deceived has the upper hand:

If the seller charged six for something worth five, the buyer has the upper hand. He can demand all his money back (voiding the sale), or the overcharge (and the sale stands).

If he charged five for something worth six, the seller has the upper hand. He can demand the item back, or the undercharge.