Commentary for Bava Kamma 6:5
הַמַּדְלִיק אֶת הַגָּדִישׁ, וְהָיוּ בּוֹ כֵלִים וְדָלָקוּ. רַבִּי יְהוּדָה אוֹמֵר, יְשַׁלֵּם מַה שֶּׁבְּתוֹכוֹ. וַחֲכָמִים אוֹמְרִים, אֵינוֹ מְשַׁלֵּם אֶלָּא גָּדִישׁ שֶׁל חִטִּין אוֹ שֶׁל שְׂעֹרִים. הָיָה גְדִי כָפוּת לוֹ וְעֶבֶד סָמוּךְ לוֹ וְנִשְׂרַף עִמּוֹ, חַיָּב. עֶבֶד כָּפוּת לוֹ וּגְדִי סָמוּךְ לוֹ וְנִשְׂרַף עִמּוֹ, פָּטוּר. וּמוֹדִים חֲכָמִים לְרַבִּי יְהוּדָה בְּמַדְלִיק אֶת הַבִּירָה, שֶׁהוּא מְשַׁלֵּם כָּל מַה שֶּׁבְּתוֹכוֹ, שֶׁכֵּן דֶּרֶךְ בְּנֵי אָדָם לְהַנִּיחַ בַּבָּתִּים:
If one lit a stack [If he lit it within his own domain and it spread to his neighbor's], and there were within it vessels and they burned, R. Yehudah says: He pays for what is hidden, [R. Yehudah holding one liable for tamun ("hidden") damages in fire, not expounding (Exodus 22:5): "or the standing corn" — Just as the standing corn is in the open, so (there is liability for) all that is in the open.], and the sages say: He pays only for a stack of wheat or barley. [For they expound "or the standing corn" and exempt tamun damages in fire. It is just that they assess the space of the vessels as if it were (part of) the stack, and he pays for that part according to the space taken up by the vessels. And from what is stated below, "And the sages concur with R. Yehudah that when one sets fire to another's house he must pay for everything that is in it," the Gemara infers that R. Yehudah and the sages differ also in an instance where one sets the fire in his neighbor's domain, R. Yehudah holding that he pays for everything within it, even a purse, and the rabbis holding that for those vessels which it is customary to hide in a stack, such as threshing sledges and cattle gear, he pays; but for vessels which it is not customary to hide in a stack, he does not pay. The halachah is in accordance with the sages.] If a goat were bound in it and a bondsman close to it, and he were burned with it, he is liable. If a bondsman were bound in it and a goat close to it, and he were burned with it, he is not liable. [For animals are also included in "or the standing corn." And he is not to be exempt from payment by virtue of receiving greater punishment (kam leih biderabbah mineih), for he is not liable for the death of the bondsman. For since he was not bound, he should have run away, and he is liable neither to be put to death nor to pay for him. But if the bondsman were bound in it, he is exempt even for the goat and the stack, for he is put to death for the death of the bondsman, and kam leih biderabbah mineih obtains. (With the goat, "bound" or "unbound" makes no difference. It is mentioned only by way of "bondsman," where it is relevant)]. And the sages concur with R. Yehudah that when one sets fire to another's house he must pay for everything that is in it, for it is customary for men to place vessels in houses. But in a stack, where it is customary to place only things like threshing sledges and cattle gear, even if he lit the fire in his neighbor's domain, he pays, according to the sages, only for those things that it is customary to hide in a stack.] If a spark went out from under the hammer and caused damage, he is liable. If a camel laden with flax passed through the public domain, and its flax entered a shop and was ignited by the shopkeeper's lamp and set the building afire, the owner of the camel is liable. If the shopkeeper placed his lamp outside, the shopkeeper is liable. R. Yehudah says: With a Channukah lamp, he is not liable, [because he is engaged in the performance of a mitzvah. The halachah is not in accordance with R. Yehudah.]
Rambam on Mishnah Bava Kamma
Bartenura on Mishnah Bava Kamma
English Explanation of Mishnah Bava Kamma
If a kid was fastened to it [to the stack] and a slave stood near by, and they were burnt with it, he is liable. If there was a slave fastened to it [to the stack] and a kid stood near by and they were burnt with it, he is not liable.
The Sages agree with Rabbi Judah that if a man set fire to a large building, he must make restitution for everything therein; for such is the custom among men to leave [their goods] in their houses.
The final two mishnayoth of chapter six continue to deal with damages caused by fire. We learned in the previous mishnah that a person who sets a fire is liable not just for the destruction of crops but also for the damage done to the field itself. Mishnah five deals with damages done to various things that may be on a field. Mishnah six deals with fires that may have been set accidentally.
Section one of mishnah five contains a dispute between Rabbi Judah and the sages with regards to fire damage done to utensils that were placed inside a stack of wheat. According to Rabbi Judah one is liable for the damage done to the utensils as well as the wheat (or barley) itself. According to the Sages the kindler’s liability is limited to the wheat. For the damage done to the utensils he is exempt. Section three can help us understand the basis for this dispute. There we learn that the Sages agree with Rabbi Judah that if one burns a building he is obligated also for the things left inside, because it is customary for people to leave things in buildings. In comparison, we can see that the Sages think it is not customary for people to leave things in stacks of hay. Therefore a person who burns a stack of hay is exempt if someone left in there an item that is not usually left in a stack of hay. Rabbi Judah probably assumes that it does not make a difference if people normally leave things in the place that was burnt. Since the person caused the damage he is liable in any case.
Section two deals with a case where a kid (small goat) and/or slave were found near or tied to the stack of hay and were burnt and killed in the fire. We will discuss the second clause first. Here the slave is tied to the stack of hay when he was burnt and killed. When the mishnah says that the person is not liable, the meaning is that he is not liable for monetary remuneration. The reason is that he will receive a more severe penalty for killing the slave. In Jewish law there is a principle that one cannot receive two punishments for one crime. In this case the person killed another person and caused damage to property at the same time. For killing, the person is obligated for the death penalty and therefore he cannot also receive a monetary fine. (For a different example see Bava Kamma 3:10). In the first clause the slave was only near the stack but not tied to it. Since the slave could have run away the kindler is not liable for the death penalty and therefore he will be liable for damages.