פירוש על בבא מציעא 8:2

המשאיל אומר שאולה מתה – and you are liable for its unavoidable accidents.

If one borrowed a cow, and borrowed it for half a day and hired it for half a day; or borrowed it for one day and hired it for the next; or if he borrowed one cow, and hired another and the cow died if he that lent the cow says: “It was the borrowed cow that died”, [or] “On the day when it was borrowed it died”, [or] “During the time when it was borrowed it died” and the other one says: “I don’t know”, (1) he is liable. If the hirer says, “It is the hired one that died”, [or] “On the day when it was hired it died”, and the other says, “I do not know”, (1) he is not liable. If the one says, “It was borrowed”, and the other says, “It was hired”, (1) the hirer must take an oath that it was the hired one that died. If the one says, “I do not know”, and the other says, “I do not know”, (1) they share in the loss. There are three possible scenarios mentioned in this mishnah 1) Shimon borrows from Reuven a cow for half a day and rents the same cow for the other half of the day; 2) Shimon borrows the cow for one day and hires it on the next day; 3) Shimon borrows from Reuven one cow and rents a different cow. If the cow should die a natural death it will be in Shimon’s best interest that the cow died while it was being hired, since a hirer does not pay in cases of natural death. It will be in Reuven’s best interest if the cow died while being borrowed since borrowers do pay in cases of natural death. Our mishnah delineates the possible claims of Reuven and Shimon and the law in each case. Case a: If Reuven, who lent the cow, claims that he is certain that the cow died while being rented or that the rented cow died and Shimon claims that he doesn’t know, Shimon is liable. This goes according to the general principle that one who claims that he is certain has a stronger claim then one who claims he is not certain (see Steinsaltz reference guide, page 172. Case b: Similarly, if Shimon claims that he is sure that the cow died while being borrowed or that the borrowed cow died and Reuven claims that he does not know, Shimon is exempt. Since Shimon is certain that the borrowed cow died and Reuven doesn’t know, Shimon’s claim is stronger. Case c: If they disagree and each claims that he is certain, Shimon takes an oath that it died while it was being hired and he is exempt from making restitution. This is based on the principle that the burden of proof is upon the plaintiff. Since in this case Reuven is the plaintiff and he cannot prove his claim, Shimon is exempt. Case d: If both claim that they are uncertain then they split the loss of the cow. In this case Shimon will pay Reuven half the value of the cow.

איני יודע – lest it died while rented out, and am exempt from the unavoidable accidents.

חייב – It is not possible to establish our Mishnah as it implies, for we hold that my Maneh is in your hands, and the other says, that he doesn’t know [how the animal died] and he takes an equitable oath (see Shevuot 40b – which is applied, if one who is sued for a debt, denies the latter entirely, in contradistinction to the legal oath which is required when the defendant admits a part of the claim. It being presumed that nobody will go to law unless he has a claim, it is a matter of equity to put the opponent to an oath, to which he may in return put the claimant) that he does not know [how the animal died – if it had been borrowed or tented] and is exempt from payment/penalty. For this reason, we establish in the Gemara (Bava Metzia 98a) that where there is the business of an oath that is Torah mandated between them, such as where [the lender] says to him: I transferred to you two cows, one day as borrowed and the other day as a rental, and both of them (i.e., the cows) died while they were borrowed. And the borrower said to him (i.e., the lender), one of them, yes, at the time while it was borrowed it died. But one of them (i.e., the cows), I don’t know. And this like someone who partially admits to the claim and he is liable for an oath. And because he cannot take an oath, he pays. And it is similar to [the case of] my Maneh is in your hands, and the other responds, How is this? Fifty (i.e., one-half) I know about and fifty (i.e., the other half) I don’t know [anything] about. He is required to take an oath but he is not able to take an oath, and because he is unable to take an oath, he must pay.

ישבע השוכר ששכורה מתה – this also is impossible to establish as it implies. And we hold that if one claimed “wheat” and the other admitted to him “barley,” he is exempt even from the cost of the barley. And that is so – that what he admitted to him was not what the other claimed, and what he claimed he (i.e., the other) did not admit to him. And what place is there for an oath? For this we have established in the Gemara (Bava Metzia 98b – a “rolling oath.” The lender can plea: “Even on your own plea, you must still swear that the animal died naturally, not through your negligence” – which rejects the ruling of Rami bar Hama’s ruling that no oath is imposed at all upon bailees, even when they plead loss, theft, death, etc., unless there is also a partial rejection of the claim. The bailee is bound to swear another oath – that the hired one and not the borrowed one has died is administered. The superimposed oath is Biblical, not Rabbinic. See also Sotah 18a). In that he (i.e., the lender/person who rents out the animal) says to the borrower/renter: Swear to me the oath of the bailees that you are required to swear, that she (i.e., the animal) died naturally, for the deponent’s statement is accepted as true on the ground that, if he had intended to tell a lie, he might have invented one more advantageous to his cause – that he could have taken an other that it died naturally for if he made a claim also that via a rolling oath, that she died while rented out.

יחלוקו – Our Mishnah is [according to] Sumachus, who stated that monies that are placed in doubt should be divided, and it is not the Halakha, for the Halakha is: “He who wants to exact [compensation] from his fellow bears the burden of proof” (see Mishnah Bava Kamma, Chapter 3, Mishnah 11), and the the one appealed to must take an oath that he doesn’t know and is exempt.