NAZIR 55 (3 Cheshvan) - dedicated l'Iluy Nishmas Shlomo Mordechai ben Yakov Sobol, in honor of his son Aaron.

1) THE REASON FOR "TUM'AS ERETZ HA'AMIM"
QUESTION: The Gemara discusses whether the Tum'ah of Eretz ha'Amim is Metamei because of "Avira" (the air) or because of "Gusha" (the ground). If it is Metamei because of "Avira," this means that the Tum'ah is more invasive than the Tum'ah of a Mes, such that even if a person travels into Eretz ha'Amim while completely enclosed (with a partition between him and the ground) he still becomes Tamei because the air itself is Metamei him.
The Gemara asserts that whether the "Avira" is Metamei or the "Gusha" is Metamei is the subject of a dispute between Rebbi and Rebbi Yosi b'Rebbi Yehudah, who disagree about whether a person who travels to Eretz ha'Amim in an enclosed chest or box ("Shidah, Teivah, or Migdal") is Tahor or Tamei. The Gemara concludes that both Rebbi and Rebbi Yosi b'Rebbi Yehudah maintain that Eretz ha'Amim is Metamei because of "Avira." Rebbi Yosi b'Rebbi Yehudah states that a person in a box is Tahor because such a form of travel is not common ("Lo Shachi'ach") and therefore the Rabanan did not enact a Gezeirah to prohibit it with Tum'ah.
Why does the Gemara conclude that both Rebbi and Rebbi Yosi b'Rebbi Yehudah agree that Eretz ha'Amim is Metamei because of "Avira"? Perhaps they both agree that Eretz ha'Amim is Metamei because of "Gusha." A chest or box is an "Ohel Zaruk," a moving (or "thrown") container, which is not considered an Ohel to serve as a partition between the Tum'ah outside and the person inside according to both Rebbi and Rebbi Yosi b'Rebbi Yehudah (according to Tosfos' first explanation; see following Insight). Therefore, the box does not serve as a partition between the occupant and the ground, and the ground should be Metamei him through Tum'as Ohel since he is traversing over Tum'ah. Nevertheless, Rebbi Yosi b'Rebbi Yehudah says that he is Tahor because it is a very uncommon way of traveling into Eretz ha'Amim. Why does the Gemara say that they agree that Eretz ha'Amim is Metamei specifically because of "Avira"? (MISHNEH L'MELECH, Hilchos Tum'as Mes 11:1)
ANSWERS:
(a) The MISHNEH L'MELECH suggests that the Gemara does not mean that both Tana'im maintain that Eretz ha'Amim is Metamei because of "Avira." Rather, the Gemara means that the dispute between Rebbi and Rebbi Yosi b'Rebbi Yehudah is unrelated to whether Eretz ha'Amim is Metamei because of "Avira" or because of "Gusha." They both may agree that it is Metamei because of either "Avira" or "Gusha."
(b) Perhaps if Eretz ha'Amim is Metamei because of "Gusha," the logic that "the Rabanan did not enact a Gezeirah for an uncommon way [of traveling]" would not apply here. Only if Eretz ha'Amim is Metamei because of "Avira" is it possible that the Gezeirah does not apply in all cases.
What is the logic behind this?
There is a basic difference between the two possible ways in which Eretz ha'Amim is Metamei. If the Gezeirah that Eretz ha'Amim is Metamei is because of "Gusha," this means that the Gezeirah is based on the concern that a source of Tum'ah (such as a corpse) is concealed within the ground of Eretz ha'Amim, and thus every part of Eretz ha'Amim must be treated as though a corpse is buried in it.
In contrast, if the Gezeirah is because of "Avira," the Rabanan decreed that Eretz ha'Amim is Tamei for an entirely different reason. The Rabanan instituted Tum'ah in Eretz ha'Amim merely to prevent people from leaving Eretz Yisrael. They instituted the Tum'ah in a way that Eretz ha'Amim will be Metamei a person whenever he enters Chutz la'Aretz, even when a partition separates him from the ground (see Tosfos 54b, DH Eretz ha'Amim).
If the Gezeirah of Tum'as Eretz ha'Amim is because of "Gusha," the Gezeirah still applies even if a person travels to Eretz ha'Amim in an unusual manner. As far as the Tum'ah is concerned there is nothing unusual about how the Tum'ah reaches him. Tum'as Mes is Metamei any person who walks or traverses over it (regardless of the means of transportation he uses). However, if the Gezeirah of Tum'as Eretz ha'Amim was instituted to prevent people from traveling to Eretz ha'Amim, then if one travels in an unusual way perhaps he is excluded from the Gezeirah since his mode of transportation is unusual, a "Milsa d'Lo Shachi'ach."
2) THE DISPUTE BETWEEN REBBI AND REBBI YOSI B'REBBI YEHUDAH IN THE CASE OF "OHEL ZARUK"
QUESTIONS: The Gemara cites a Beraisa in which Rebbi and Rebbi Yosi b'Rebbi Yehudah disagree about whether a person who enters Eretz ha'Amim in an entirely enclosed container ("Shidah, Teivah, or Migdal") becomes Tamei with Tum'as Eretz ha'Amim. The Gemara suggests that their dispute may revolve around whether an "Ohel Zaruk" (a moving Ohel) is considered an Ohel or not. Rebbi, who rules that the person is Tamei, maintains that an Ohel Zaruk is not considered an Ohel.
The Gemara cites another Beraisa in which Rebbi Yosi b'Rebbi Yehudah states that when a person throws a container filled with smaller vessels over a Mes, all of the vessels inside the container become Tamei. If the container is not thrown but is standing still, all of the vessels inside the box remain Tahor.
TOSFOS presents two explanations for the Gemara. According to the first explanation, the Gemara cites the second Beraisa as a refutation of the Gemara's initial understanding of the dispute between Rebbi and Rebbi Yosi b'Rebbi Yehudah. The Gemara means to say that Rebbi Yosi b'Rebbi Yehudah cannot maintain that the person is Tahor because of "Ohel Zaruk Shmei Ohel," because he says explicitly (in the second Beraisa) that when an Ohel is thrown over a Mes the vessels inside become Tamei. The Gemara continues and suggests other ways of explaining the dispute between Rebbi and Rebbi Yosi b'Rebbi Yehudah.
According to the second explanation of Tosfos, the Beraisa is cited as proof that the Gemara's understanding of the dispute is correct. Rebbi Yosi b'Rebbi Yehudah indeed maintains that an Ohel Zaruk is a valid partition between the person and the ground. Since an Ohel Zaruk is an Ohel, in the second Beraisa he states that when a box is placed on something, such as on the back of a person or an animal, the box does not become Tamei even when the person or animal passes the box over a Mes. However, when the box passes over a Mes as it flies through the air, even Rebbi Yosi b'Rebbi Yehudah agrees that the box does not protect the objects inside from becoming Tamei, since an object in flight cannot be an Ohel. Although this explanation is not refuted, the Gemara continues and suggests other explanations for the Machlokes.
Tosfos leaves a number of basic questions on the first explanation unanswered. Tosfos cites the Gemara in Eruvin and in Chagigah which assumes that Rebbi and Rebbi Yosi b'Rebbi Yehudah in the Beraisa do argue about whether an Ohel Zaruk is considered an Ohel. According to the first explanation, why does the Gemara in Eruvin and Chagigah disregard the Beraisa quoted here which disproves this understanding of their dispute? (The RITVA in Eruvin rejects this explanation of Tosfos because of this question.)
Moreover, the Gemara's final explanation for the Machlokes between Rebbi and Rebbi Yosi b'Rebbi Yehudah is that they agree that the Rabanan decreed Tum'ah only on the "Gusha" (ground) of Eretz ha'Amim. Accordingly, a person who travels there in a box should be Tahor. Rebbi, however, says that he is Tamei because of a Gezeirah "Shema Yotzi Rosho v'Rubo" -- lest he extend his head and most of his body out of the box into Eretz ha'Amim.
If Rebbi Yosi b'Rebbi Yehudah agrees that an Ohel Zaruk is not an Ohel, why does he rule that the person inside the box is Tahor? Even if the Rabanan decreed Tum'ah only on the "Gush" of Eretz ha'Amim, they certainly decreed Tum'ah on a person who either touches (Maga) or travels over (Ohel) the "Gush" of Eretz ha'Amim. (See TOSFOS to 54b, DH Eretz ha'Amim.) Since the Ohel Zaruk is not considered a partition between the person and the ground, the person inside is considered as though he traverses directly over the ground of Eretz ha'Amim and he should be Tamei! (Although the previous answer in the Gemara suggests that Rebbi Yosi b'Rebbi Yehudah maintains that the person is Tahor because traveling in a box is very uncommon ("Milsa d'Lo Shachi'ach"), the Gemara's last answer clearly offers an alternate explanation and does not rely on the logic of "Milsa d'Lo Shachi'ach.") TOSFOS in Chagigah rejects this explanation because of this question.
ANSWER: Even according to the first explanation, Rebbi and Rebbi Yosi b'Rebbi Yehudah indeed may argue about an Ohel Zaruk. However, their argument does not involve a case of a person who carries a box which contains another person or vessels over a Mes. Rather, their argument involves a box which contains a person or vessels and which is stationary ("Munachas"). Rebbi Yosi b'Rebbi Yehudah maintains that an "Ohel Zaruk" -- a portable Ohel which is moved often -- is considered an Ohel while it is stationary but not while it is moving. Rebbi argues and maintains that since the Ohel is normally moved from place to place, even when it is stationary it cannot be considered an Ohel. Their dispute applies only in a case of "Munachas," in which the Ohel is not moving. This is how the Gemara in Eruvin and Chagigah understands the argument between Rebbi and Rebbi Yosi b'Rebbi Yehudah in the case of "Shidah, Teivah, u'Migdal" in Eretz ha'Amim.
The Beraisa discusses an Ohel Zaruk which is presently stationary and is being held above the ground at the border between Eretz Yisrael and Chutz la'Aretz. When a person walks into it from Eretz Yisrael, Rebbi Yosi b'Rebbi Yehudah rules that he is Tahor because the box is stationary ("Munachas") and is considered an Ohel. Rebbi rules that the person is Tamei because it is an Ohel Zaruk, an Ohel made for transporting. The Gemara here, in contrast, wants to avoid having a Machlokes Tana'im about a stationary Ohel. The Gemara assumes that when an Ohel is not moving, no Tana would be Metamei the box just because it is made to move. Therefore, the Gemara here does not remain with the explanation that Rebbi and Rebbi Yosi b'Rebbi Yehudah argue about the status of an Ohel Zaruk. Rather, the final explanation of the Gemara assumes that the box (the Ohel) is held above the ground at the border of Eretz Yisrael, and since it is stationary both Rebbi and Rebbi Yosi b'Rebbi Yehudah should maintain that its contents are Tahor. The only reason why Rebbi says that the contents are Tamei is the Gezeirah of "Shema Yotzi Rosho v'Rubo."

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