1) THE HEIGHT OF THE RINGS ON THE "MIZBE'ACH"
QUESTION: The Gemara explains that the Leviyim, who were ten Amos tall, carried the Mizbe'ach, which was ten Amos high, with 3 1/3 Amos of it above the height of their shoulders, and 6 2/3 Amos of it below the height of their shoulders (which left about twenty Tefachim between the ground and the bottom of the Mizbe'ach). Consequently, the rings in which the poles were inserted must have been 6 2/3 Amos from the bottom of the Mizbe'ach.
However, RASHI (to Shemos 27:7) explains that the rings were on the one-Amah-wide Michbar (the netting around the Mizbe'ach), and the Michbar reached until half of the height of the Mizbe'ach (Shemos 27:4). Since the Michbar was one Amah wide, the rings must have been only six Amos from the bottom of the Mizbe'ach, and not 6 2/3 Amos!
Second, why does the Gemara need to say that things that are carried with poles are customarily carried with one third of the height of the object above the poles and two-thirds below the poles? The verse itself teaches that six Amos were below the poles! (CHASAM SOFER AL HA'TORAH)
ANSWER: The CHASAM SOFER answers that perhaps the rings were elongated (oval shaped) so that the poles were two-thirds of an Amah (or more) above the level of the Michbar.

92b----------------------------------------92b

2) TWO PEOPLE WHO PERFORM A MELACHAH TOGETHER
QUESTION: The Gemara says that according to Rebbi Shimon, two people who perform a Melachah together are exempt, whether or not each one was able to perform the Melachah alone. Rebbi Shimon's source is the verse, "ba'Asosah" (Vayikra 4:27). Rebbi Yehudah argues and maintains that they are exempt only when each one is able to do the Melachah alone, but when each one is unable to do the Melachah alone, they are both Chayav. Rebbi Yehudah derives his opinion from the same verse, "ba'Asosah."
Why does Rebbi Yehudah limit the exclusion of "ba'Asosah" to a case in which each individual is able to do the Melachah by himself? Rebbi Shimon's way of understanding the verse -- that whenever more than one person does a Melachah, no one is Chayav -- seems more straightforward.
ANSWERS:
(a) RASHI (DH v'Rebbi Yehudah Poter) explains that the Torah's intention is to broaden the category of k'l'Achar Yad. When two people do a Melachah together when each one is fully capable of doing the Melachah alone, that is considered an unusual manner of doing the Melachah, and they are exempt. When neither one is able to do the Melachah alone, doing it together is considered the normal manner of performing the Melachah, and they are Chayav.
(b) RASHI later (93a, DH Mipnei she'Yecholah) explains that Rebbi Yehudah maintains that each person is considered to be Mesaye'a if he is able to do the Melachah alone. When neither one is capable of doing the Melachah by himself, each one's contribution to the act of Melachah is not considered Mesaye'a, but is considered a full act of Melachah.
(c) The RITVA cites RABEINU MOSHE BEN RABEINU YITZCHAK who explains that when each person is unable to do the Melachah by himself, he is Chayav for the share of the Melachah that he does, because each one is doing as much as he can. When each one is able to do the entire act of Melachah alone, he is exempt, because neither one puts all of his strength into the act.
(d) The Ritva offers a second explanation. When the two people who do the Melachah are each unable to do the Melachah alone, the Torah considers the Melachah that was accomplished to be a significant Melachah based on the principle of "Ach'shevei," because the Melachah could not have been accomplished without the participation of each person.
3) SINNING AS A PAIR
OPINIONS: The Gemara discusses the principle that "when two people perform a Melachah together, they are exempt." Does this principle also apply to other Isurim besides Shabbos?
(a) The PNEI YEHOSHUA in here maintains that this principle applies only to Shabbos. The Gemara in Zevachim (108b) teaches that when two people offer a Korban outside of the Azarah together, they are both Chayav to bring a Korban for their sin, in contrast to the law with regard to two people who perform a Melachah together.
The Pnei Yehoshua points out that the Gemara here cites proof for the principle from the laws of Zavim, which are unrelated to Shabbos, and thus the principle does seem to apply to laws other than Shabbos. The RASHBA (Teshuvos 1:28) addresses this question and writes that the exemption from a Korban for two people who sinned together applies only to "Zav and Shabbos" (it applies to Zav because of the unique rule that a Zav makes an object Tamei with Tum'as Midras only when it supports most of his weight).
(b) However, the Gemara says that two people who do a Melachah together are exempt because of the verse, "ba'Asosah." That verse is written with regard to the obligation to bring a Korban Chatas. It is not written in the specific context of Shabbos. It appears, therefore, that the limitation of accountability derived from "ba'Asosah" should apply to all transgression, and not only to Shabbos. Similarly, the Gemara in Zevachim (108b) derives from a verse that two people who offer a Korban outside of the Azarah are Chayav. The fact that a separate verse is required to teach that two who transgressed that Aveirah together are Chayav implies that without such a verse, they would be exempt because of the verse of "ba'Asosah."
The RITVA in Kidushin (43a) indeed writes that this exemption applies to every transgression, except for a case in which two people carried a limb of a sanctified animal outside the Azarah (as derived from the verse cited in Zevachim). It is likely that the Rashba quoted above does not argue with the Ritva. A close examination of his words shows that he may intend to say only that "Shenayim she'Asa'uha" does not apply to carrying a Mes, but it does apply to Isurim, as the Ritva says.
(c) HA'GAON RAV YISRAEL ZEV GUSTMAN zt'l in KUNTRESEI SHI'URIM (Bava Kama 13:11-12) cites the MEKOR CHAYIM (OC 266) who adds that this exemption applies only to Chiyuvei Chatas, but not to Chiyuvei Lav. This is logical, considering that the verse "ba'Asosah" is written with regard to Korban Chatas. HA'RAV HILLEL RUVEL shlit'a pointed out to me that RASHI clearly makes such a distinction in Pesachim (85b, DH d'Avad Lei). It is probable that the Ritva and Rashba cited above agree with this distinction as well. The Mekor Chayim therefore concludes that two people who perform the Melachah of Mechamer (which is only a Lav) together are Chayav. (M. KORNFELD)

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