(Mishnah): If Reuven recognized his Kelim or Sefarim with Shimon [who claims that he bought them], and there were rumors that Reuven was robbed, Shimon swears how much he paid, and Reuven pays this and takes them back from Shimon.

If not [for the rumors], Reuven cannot force Shimon to sell them. Perhaps Reuven sold them, and Shimon bought from the buyer!

(Gemara - R. Ba bar Mamal): According to letter of the law, Shimon should not swear. Why did [Chachamim] say that he swears? It is lest people commonly buy from thieves. (One is reluctant to buy if he thinks that later he will need to swear in order to get back the money that he paid.)

(R. Yehoshua ben Levi): Our Mishnah discusses when there were rumors that his Seforim were stolen.

(Rav): [Reuven] must bring a proof that [the one who sold to Shimon] was in [Reuven's] house that night. (If not, we are concerned lest Reuven sold them, and falsely claimed that he was robbed.)

(Asi): If [Shimon] claimed and said 'I bought them from Ploni' (not the suspected thief), he is believed [to receive what he paid without a Shevu'ah - NESIVOS YERUSHALAYIM, HA'GAON RAV C. KANIEVSKY, SHLITA].

A case came in front of R. Nasa, and he did not accept this claim.

Question: Does [R. Nasa] argue [with Asi]?

Answer: (No.) The one [whom he said sold them] was very poor (we estimate that he did not have enough money to buy the theft). Therefore, he did not accept the claim. (MAHARA FULDA, SEDEI YEHOSHUA)

(Mishnah): If Levi was carrying a barrel of wine, and Yehudah was carrying a jug of honey, and Yehudah's barrel cracked, and Levi spilled out his wine and saved the honey, he is paid only like a worker (he is not compensated for the wine that he forfeited);

If Levi said 'I will save your honey and you will pay for my wine', Yehudah must give to him.

(Gemara - Beraisa): If two were in the Midbar, one had a barrel of water, and the other had a barrel of honey, and the barrel of water cracked, it is a stipulation of Beis Din that Levi spill out his honey and save the water, for water sustains people in the Midbar, and honey does not.

(Beraisa): If a worker or Oni ascended a tree [to harvest it, or take the Pe'ah], and he broke a branch - if it is normal for workers [or Aniyim] to ascend [such a tree to do so], he is exempt. If not, he is liable.