Bava Kamma, Chapter 5, Mishnah 5. From here, we proceed to discuss the primary category of damage known as Bor (a Pit).
The First Case - The Potter's Pots:
The Mishnah begins: "Hakadar shehichnis kederosav lachatzer baal habayis shelo birshus" - a potter who brings his pots into another's courtyard, his neighbor's for example, without obtaining permission. These are the halachos:
"Veshibarsan behemto shel baal habayis - patur" - the homeowner, who has no idea that the pots are placed in his courtyard, is exempt if his animal breaks them, since he can claim: What reason did you have to place your pots in my courtyard? They are not my responsibility.
"Ve'im huzkah bahen - baal hakederos chayav" - if the animal is injured by the pots, the one who placed them there is responsible for the damage. This is like one who digs a pit in his fellow's courtyard, and he is liable for the damage caused to animals.
It is worth noting: Even though the homeowner is exempt when his animal breaks the pots, he has no right to break them himself. If he does so, he is obligated to pay in full, because despite the pots being placed there without permission, a person may not break his fellow's vessels, and if he breaks them - he is fully liable under the category of a human damager.
"Ve'im hichnis birshus - baal hachatzer chayav" - when the potter obtained permission to bring his pots into the courtyard, the owner of the courtyard becomes liable for the damage his animals cause to the pots. The Tanna holds that one who gives permission to his fellow to store items on his property implicitly agrees - even without it being stated explicitly - to guard the items and function as a watchman. While his status is an unpaid watchman (shomer chinam), he nevertheless assumes a certain degree of responsibility.
As we will see in the next Mishnah, Tannaim dispute this matter. According to Rabbi, the mere granting of permission to use the courtyard does not include an agreement to guard the items and protect them from damage, not even from the animals of the courtyard owner. The halachah is ruled in accordance with Rabbi. However, here, in the words of our Tanna, a dissenting opinion has not yet been presented.
The Second Case - Produce in the Courtyard:
The Mishnah continues with a very similar case, which is essentially identical, except that this time it deals with produce rather than earthenware vessels:
"Hichnis peirosav lachatzer baal habayis shelo birshus, va'achalatan behemto shel baal habayis - patur" - the neighbor brings a sack of wheat into his fellow's courtyard without permission, and the cow of the courtyard owner eats it. The owner of the cow is exempt, since he can claim: Why did you bring your wheat into my courtyard, where my animals are found?
"Huzak bahen baal habayis - baal hapeiros chayav" - if damage is caused on account of the produce, for example, the animal of the courtyard owner twisted its leg on the pile of wheat, the one who stored the produce there is responsible and pays full damages under the law of Bor (a Pit), since the produce was placed there without permission.
"Hichnis birshus - baal hachatzer chayav" - when permission is granted to store the wheat, the owner of the courtyard is responsible for damage caused to it, such as if his cow ate it. This is because, according to this Tanna, granting permission for storage implicitly includes an agreement to guard the items. As mentioned, this is not the practical halachah.
Why Were Both Cases Taught?
The two cases are fundamentally identical, hence the question: why are both required? The answer is that one might have thought the law for earthenware vessels is different from the law for produce, because earthenware vessels are damaged much more easily, and they are also more likely to cause damage. The Mishnah comes to teach that this is not so, and the law is identical in both cases.
This concludes the first Mishnah, but do not jump to conclusions, as in the next Mishnah we will see a law that changes this picture slightly.