QUESTION: The Beraisa discusses a case in which one digs a Bor nine Tefachim deep and another person comes and extends it to ten Tefachim deep (thereby rendering it capable of killing). The Rabanan maintain that only the second person is liable for damages and fatalities. Rebbi maintains that if the Bor kills, only the second person is liable, since the nine Tefachim that the first person dug are not lethal. However, if the Bor damages, both are liable.

Later (51a), the Gemara cites another Beraisa that states that if one digs a Bor ten Tefachim deep, a second person extends it to twenty Tefachim, and a third person deepens it to thirty Tefachim, they are all liable. The Gemara asks that a different Beraisa states that when one digs a Bor ten Tefachim deep and someone else puts decorative plaster on the walls of the Bor, only the second person is liable. RASHI (DH Siyed) explains that when the Bor was dug originally, it was wide and therefore did not possess much Hevel (bad air, the damaging component of a Bor according to Rav, see 50b). The second person who plastered and decorated the walls made the Bor narrower and thereby added Hevel. The Gemara asks, why are all of the diggers liable in the case of a Bor which was extended by ten Tefachim twice, while this Beraisa says that only the person who plastered the Bor is liable?

The Gemara suggests that the Beraisa which says that each person who extended the Bor is liable follows the opinion of Rebbi, and the other Beraisa follows the opinion of the Rabanan. The Gemara rejects this suggestion and asserts that in fact the Rabanan agree with the Beraisa which obligates all three diggers, since all three dug a Bor capable of killing. In contrast, in the first Beraisa (which discusses a nine-Tefach Bor that was extended to ten Tefachim) the Rabanan maintain that the first digger is exempt even from damages because he dug only a nine-Tefach Bor which was unable to kill.

The Gemara says that similar logic applies to the last Beraisa. The first digger is exempt even though he dug a Bor of ten Tefachim, since it did not contain enough lethal Hevel because it was so wide. Only when the second person plastered it and made it narrow did it gain its lethal capability.

TOSFOS (DH Bor) explains that according to the original suggestion of the Gemara that the second Beraisa follows Rebbi and the third follows the Rabanan, even if the second digger deepens the Bor to only eleven Tefachim (from ten) he would be liable.

Why does Tosfos make this comment only according to the Gemara's suggestion that the second person who extends a Bor to eleven Tefachim is liable? Tosfos implies that according to the Gemara's conclusion, only the person who extends a Bor to eleven Tefachim, not to twenty, is exempt. Is this in fact the law?

ANSWER: The RASHBA explains that the Gemara initially understands that when the Beraisa says that the person who plastered the Bor is liable, it means that the Bor did not need to undergo a major modification in order for that person to become liable. Even a small change sufficed to make that person liable. Accordingly, if the person who plastered the Bor is liable, in the case of a second digger who deepened a Bor, that second person would not have to dig another ten Tefachim in order to be liable. He should be liable even if he digs only one Tefach more. However, when the Gemara answers that a major action is required to make the second person liable for the damages caused by the Bor, it means that the person who plastered the Bor is liable because he turned the Bor into one that can kill. Similarly, a person who extends a ten-Tefach Bor is liable only if he does a major action -- he deepens the Bor by another ten Tefachim which are capable of killing on their own.

(See also MAHARSHA and MAHARSHAL in CHOCHMAS SHLOMO who explain Tosfos in this manner. See also see MAHARAM.) (D. BLOOM, Y. MONTROSE)

QUESTION: The Mishnah (51a) states that two partners own a Bor and both passed by it and did not cover it, the second partner who passed by is liable for the damage that it subsequently causes.

The Gemara (51b) asks, when does the exemption of the first partner begin? RASHI (DH v'Rishon) explains that it is obvious that when the Mishnah says that the partners passed by, it is not meant literally; if they passed by one after the other, there is no reason why the first should be exempt. After all, he was just as negligent as the second partner for not covering the Bor. Rather, when the Mishnah says that each "passed by," it means that they actually used the Bor. In what case, then, would the first partner be exempt?

The Gemara gives two answers. The first answer is that when the first partner leaves the second one using the Bor, he is exempt. The second answer is that the exemption begins only when he hands over the cover of the Bor to his partner. The Gemara then cites a dispute between Tana'im which is dependent on these answers. The Beraisa states that if one person was drawing water from a Bor and his friend came and said, "Let me draw water," according to the Tana Kama the first person becomes exempt from liability once he leaves the second one using it. This view is consistent with the Gemara's first answer. Rebbi Eliezer ben Yakov disagrees and exempts the first person only when he hands over the cover of the Bor to the second person. His view is consistent with the Gemara's second answer.

The Gemara explains that the Rabanan and Rebbi Eliezer ben Yakov disagree about whether Bereirah works. "Bereirah" refers to a retroactive clarification of the status of a past event based on an event which occurs in the future.

Rebbi Eliezer ben Yakov maintains "Yesh Bereirah," and thus when each partner draws water he may say that he is drawing his own water. RASHI (DH v'Ha) explains that the water that the second person draws is considered as though that water always belonged to him. Since he is not using the first partner's water, he is not responsible for guarding the first partner's portion of the Bor. Consequently, if the Bor damages they are both liable. The second person becomes the sole guardian of the Bor only when he receives the cover.

The Gemara adds that Rebbi Eliezer ben Yakov and the Rabanan are consistent with their respective positions in a different dispute. The Mishnah in Nedarim (45b) teaches that when partners in a courtyard vow not to derive benefit from each other, according to the Rabanan neither partner may enter the courtyard. Rebbi Eliezer ben Yakov maintains that each partner is permitted to enter his own part of the courtyard. The Rabanan maintain "Ein Bereirah," and thus when each partner uses the courtyard there is no retroactive clarification that the part that he is using now was the part he bought as his portion at the time of the original Kinyan. Consequently, he is using not only his portion but his friend's portion as well. Rebbi Eliezer ben Yakov maintains "Yesh Bereirah," and thus when each partner uses the courtyard there is retroactive clarification that the part that he is using now was the portion which he owned from the beginning. Accordingly, he is using only his portion and not his friend's.

The Gemara in Nedarim (46b) concludes that the Halachah follows Rebbi Eliezer ben Yakov, and each partner is permitted to enter his own portion of the courtyard. This implies that the Halachah is "Yesh Bereirah." However, the Gemara in Beitzah (38a) concludes that for matters of Torah law the Halachah is "Ein Bereirah," and for matters of rabbinical law the Halachah is "Yesh Bereirah."

However, the prohibition against deriving benefit in the case of a vow is a Torah prohibition. Why, then, does the Halachah follow Rebbi Eliezer ben Yakov, who says that each partner may enter the courtyard because he is considered as though he enters his own portion? (See RAN to Nedarim 45b, DH v'Ika, and Insights there.)

ANSWER: The RE'AH answers in the name of the RAMBAN (cited by the NIMUKEI YOSEF) that the concept of Bereirah which the Gemara here discusses is different from the normal concept of Bereirah mentioned elsewhere.

The Gemara in Gitin (25a) discusses a case in which a person buys wine from an Am ha'Aretz (who is not trusted to separate tithes), and it is not possible for him to separate tithes before he drinks the wine. According to the opinion that "Yesh Bereirah," he may designate which quantities of wine from the barrel will later be Terumos and Ma'aseros, and he may proceed to drink the wine. He may rely on the fact that the wine which he will separate later (from the wine he leaves over and does not consume) is already considered as Terumos and Ma'aseros because of "Yesh Bereirah."

In contrast, in the case of the Gemara here, one cannot say that after the partners will divide the courtyard it will become determined that the area that each partner entered was in fact his, because each partner is using the entire courtyard. Here, the phrase "Yesh Bereirah" means that when each partner uses the courtyard, he does so because of his right to use it; he is not considered to be using his friend's part at all.

What is the logic of the Gemara? The Re'ah's explanation may be understood based on the words of the RAMBAN, as cited by the NIMUKEI YOSEF here (and by the RAN in Nedarim 45b in the name of HA'RAV RABEINU MOSHE). The Ramban explains that since the courtyard under discussion is not large enough to be divided (see Nedarim 46b), each partner may use all of the courtyard. Each partner is considered as though he enters his own portion of the courtyard. If one partner would be able to forbid the other to use any of the courtyard, this would mean that he forbids his friend to use any of the courtyard in which he is a partner. Since there is a principle that a person cannot make a property forbidden from use by the owners themselves, it is not possible for one partner to make the courtyard forbidden to the other. Accordingly, the words "Yesh Bereirah" here mean that each partner has the choice to use the courtyard because the other does not have the ability to forbid him from doing so. (D. BLOOM, Y. MONTROSE)