Rav Naḥman responds: No, he is exempt here because there are not sufficient fumes to cause death, in accordance with the opinion of Rav. Nevertheless, the impact from hitting the ground is sufficient to cause death, and therefore an ox that fell into a water channel is suspected of being a tereifa. Rava again challenges him: If so, then how is the statement: If the animal was injured by it, he is liable, to be explained? There are not sufficient fumes? Rav Naḥman said to him: There are not sufficient fumes to cause death, but there are sufficient fumes to cause injury.

Rava raised an objection to the opinion of Rav Naḥman from a mishna (Sanhedrin 45a): The structure from which the punishment of stoning was implemented was a height of two people, and it is taught in that regard in a baraita: When the two-person height of the structure is combined with his height, i.e., the height of the one being stoned, there is a total height equal to that of three people. Rava explains his objection: And if it enters your mind that there is an impact capable of causing death in a pit less than ten handbreadths deep, why do I need all of this height?

Rav Naḥman answered him: And according to your reasoning, let us make the structure a minimal ten handbreadths. Why must it have a height of two people? Rather, no proof can be brought from here, since the reason is in accordance with the opinion of Rav Naḥman, as Rav Naḥman says that Rabba bar Avuh says that the verse states: “And you shall love your fellow as yourself” (Leviticus 19:18), teaching that even with regard to a condemned prisoner, select a good, i.e., a compassionate, death for him. Therefore, the structure used for stoning is constructed sufficiently high that he dies quickly, without any unnecessary suffering.

The Gemara asks: If so, let us raise the structure even more, so that his death will be even less painful. The Gemara answers: This is not done, because if he fell from a greater height, his organs would be crushed and he would become completely disfigured, which is certainly not a way one would prefer to die.

Rava again raised an objection to the opinion of Rav Naḥman: The Torah requires constructing a parapet on the roof of one’s house to prevent anyone from falling to his death, as the verse states (Deuteronomy 22:8): “You shall not bring blood upon your house, if any man falls from it.” The term “from it” teaches that liability exists only for falling from the roof of the house, but not onto the roof of a house.

How is this so? If an area in the public domain was ten handbreadths higher than a private house and the owner did not construct a fence between his house and the public domain, and someone fell from inside the public domain onto the house, the owner of the house is exempt. By contrast, if the public domain was ten handbreadths lower than the house, and the owner did not construct a fence on his roof, and someone fell from the roof of the house into the public domain, he is liable.

And if it enters your mind that there is a sufficiently strong impact to cause death even at a height of less than ten handbreadths, why do I need the roof to be ten handbreadths high for there to be a requirement to construct a parapet? Rav Naḥman said to him: The halakha of the parapet for the roof of a house is different, since any structure less than ten handbreadths is not classified as a house, and only a house requires a parapet.

Rava objects: If that is so, i.e., if the requirement to build a parapet is limited to a house that is ten handbreadths high, then also now, where the house is ten handbreadths higher than the public domain when measured from the outside, remove the height of the ceiling and the plaster, which is an additional layer on top of the ceiling. When measured from the inside in this manner, its height is not ten. According to you, then, it is not classified as a house. Rav Naḥman said to him: It is a case where he hollowed out an extra space inside in the floor of the house so that its height would be ten handbreadths.

Rava challenges him: If so, in a situation where the house is not ten handbreadths from the outside as well, you can find a scenario where it is ten handbreadths from the inside, such as where he hollowed out extra space in the floor, thereby transforming it into a house with the required height. Why, then, would a person be exempt in this case?

The Gemara answers: Rather, the previous explanation must be entirely rejected, and this is the reasoning of Rav Naḥman when he ruled that one must suspect that the ox’s organs were crushed upon falling into the water channel. He maintains the following argument: How far is the distance from the stomach of the ox to the ground? It is four handbreadths. How deep is the water channel? It is six handbreadths. This totals ten handbreadths. Therefore, it transpires that when the ox hits the ground, it is from a height of ten handbreadths that it hits the ground, since it landed on its stomach and not on its feet.

The Gemara asks: But with regard to the mishna, which teaches: Just as a pit that has sufficient depth to cause death when falling into it is at least ten handbreadths deep, so too, any other excavations that have sufficient depth to cause death may be no less than ten handbreadths deep, why not say that a pit with six handbreadths would also be sufficient?

The Sages said in reply: The mishna is referring to a case where the animal rolled into the pit, in which case the pit would be required to have a depth of ten handbreadths. By contrast, if it fell while walking, the extra height from the ground to its stomach is included in calculating the ten handbreadths.

MISHNA: If a pit belonging to two partners was uncovered and the first partner passed by it and did not cover it, and then the second passed by it and did not cover it, the second is liable for any damage caused by means of the pit.

GEMARA: The Sages say: How can you find such a case of a pit belonging to two partners? This works out well if we hold in accordance with the opinion of Rabbi Akiva, who says that one who digs a pit on his own property and then declares the property, but not the pit, ownerless, is liable for damage. According to him, you find such a case where the courtyard belongs to both of them and the pit belongs to both of them, and they renounced ownership of their property but did not renounce ownership of their pit. In that case, both are responsible for any damage caused.

But if we hold that one who digs a pit on his own property and then declares the property, but not the pit, ownerless, is exempt from liability for damage caused, how can you find a case of a pit for which a person is liable? It can only be a case where it is located in the public domain, and how can you find a case of a pit belonging to two partners in the public domain?

If they both jointly appointed an agent and said to him: Go dig a pit for us, and he went and dug a pit for both of them, then neither is liable. This is because there is no agency for transgression, and the digger is solely responsible. And if this partner dug a pit five handbreadths deep and this partner dug five further handbreadths deep, the significance of the initial act of digging performed by the first partner has been removed. Now all responsibility rests with the second partner, who deepened the pit to ten handbreadths, which is the minimum depth for which one is liable for an animal’s death. Therefore, this is also not treated as a jointly owned pit.

The Gemara notes: This works out well according to the opinion of Rabbi Yehuda HaNasi, and you find in a case of damage that both would be liable, as the Gemara will soon explain. Therefore, it qualifies as a case of a pit belonging to two partners. But according to the opinion of Rabbi Yehuda HaNasi, the first partner is not held liable at all in a case where the pit causes an animal’s death; and according to the opinion of the Rabbis, the first partner is not held liable both in a situation where it causes death and in a situation where it merely causes damage. If so, how, can you find an instance of a pit belonging to partners?

Rabbi Yoḥanan says: This is referring to a case where they both extracted a chunk of earth from the bottom of the pit simultaneously, and thereby completed it to a depth of ten handbreadths. This, then, would constitute a pit belonging to both of them.

Having mentioned the dispute between Rabbi Yehuda HaNasi and the Rabbis, the Gemara inquires: What is the opinion of Rabbi Yehuda HaNasi, and what is the opinion of the Rabbis? As it is taught in a baraita: With regard to one who digs a pit nine handbreadths deep, and another person came and completed the digging to a depth of ten handbreadths, the latter individual alone is liable for an injury or death caused by the pit. Rabbi Yehuda HaNasi says: One follows the latter for restitution for death caused by the pit. The latter is solely liable, since only a pit of ten handbreadths renders a person liable for an animal’s death. And one follows both of them for restitution for damage caused by the pit.

The Gemara explains: What is the reason for the opinion of the Rabbis? As the verse states: “If a man shall open a pit, or if a man shall dig a pit” (Exodus 21:33), it raises the question: If he is liable for opening a covered pit that has already been dug, then is it not all the more so that he should be liable for digging a new pit? What, then, does that latter phrase add? Rather, the verse serves to include the case of one person who begins to dig a pit and after he does so, a second person continues to dig. By subsequently stating: “If a man shall dig a pit,” the Torah teaches that a new pit is effectively created by the second digger, whose digging removed, i.e., rendered irrelevant, the action of the first digger and who bears full responsibility for the pit.

And Rabbi Yehuda HaNasi could have said to you: These two clauses in the verse are both necessary, and the second clause cannot serve to teach the halakha of the sole liability of the second digger. The reason they are necessary is as we said earlier (50a), where interpretations were cited according to both Rabbi Yishmael and Rabbi Akiva. The Gemara asks: And don’t the Rabbis also agree that they are necessary for those interpretations? If so, what is the source of their opinion that responsibility for the pit rests solely with the second partner?

Rather, the previous explanation must be rejected, and this is the reason of the Rabbis: The verse states: “If a man shall dig a pit,” indicating that one person is liable, but not two. Therefore, if two people jointly created the pit, the second bears responsibility and not the first.

The Gemara asks: And how does Rabbi Yehuda HaNasi understand the phrase “if a man shall dig a pit”? The Gemara answers: He requires that phrase to teach another halakha. The phrase “if a man shall dig a pit” indicates that a person who digs a pit is liable, but one is not liable if his ox digs a pit.

The Gemara asks: And from where do the Rabbis derive this halakha? The Gemara answers that the combination of words: Man and pit, is written twice: “If a man shall open a pit, or if a man shall dig a pit.” From one phrase, the halakha is derived that a person must do the digging, and not an animal. From the second phrase, the halakha is derived that one person bears responsibility for the damage, and not two people.

The Gemara asks: And what does Rabbi Yehuda HaNasi derive from this repetition? The Gemara answers: In his opinion, since the Torah wrote this first clause using this wording, it similarly wrote this second clause in the same fashion. The repetition is for stylistic reasons, and is not meant to teach a new halakha.

The Gemara continues to ask about the opinion of the Rabbis: And even if they derive from the verse that only one person is liable for damage caused through the pit, from where do they know that the Torah intends to render specifically the latter one liable for the damage? Perhaps it is to render the first one who started the digging liable for the damage.

The Gemara answers: It should not enter your mind to suggest this, since the verse states: “And the carcass shall be for him” (Exodus 21:34). This indicates that it is the one who causes the death, i.e., the second one, who is liable, and not the first. This is because it is the second one who completed digging the necessary depth for causing death, and not the first.

The Gemara asks: But isn’t this clause: “And the carcass shall be for him,” necessary for that which Rava states? As Rava says: With regard to a disqualified consecrated ox that fell into a pit, the pit’s owner is exempt, as it is stated: “And the carcass shall be for him.” Evidently, the verse is stated with regard to a case where the carcass belongs to him. This ox, which was consecrated and subsequently disqualified, does not fully belong to anybody, since its use is restricted. Since this verse serves to teach Rava’s ruling, it cannot serve to teach about the liability of the second digger.

The Sages said in response: And can’t you learn from the words and emphasis of the verse by itself that we are dealing with the one who caused the animal’s death, even if these words are also used to derive Rava’s ruling? Therefore, the verse can serve as a source for both rulings.

On a similar subject, the Sages taught: In a case of one who digs a pit to a depth of ten handbreadths, and another comes and completes the depth to twenty handbreadths by digging an additional ten handbreadths, and another comes and completes it to thirty, they are all liable for any damage caused by this pit. The Gemara comments: And one can raise a contradiction against this from a baraita: In a case of one who digs a pit to a depth of ten handbreadths, and another came and plastered it and cemented [vekhiyyeid] it, the latter is liable for damage, and not the first.