THOUGHTS ON THE DAILY DAF
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ERUVIN 16-20 - sponsored by a generous grant from an anonymous donor. Kollel Iyun Hadaf is indebted to him for his encouragement and support and prays that Hashem will repay him in kind.
1) HALACHAH: "MAYIM ACHARONIM"
OPINIONS: The Mishnah (17a) states that even for soldiers going out to
battle, "Mayim Acharonim is obligatory." The Gemara goes on to explain the
reason for the strict obligation of Mayim Acharonim. One might have some
salt from the meal left on his fingers, and if he wipes his eyes with salty
fingers he risks blinding himself with the Sedomis-salt that is contained in
2) "PASEI BIRA'OS"
Now that we do not have Sedomis-salt in our table salt, does the obligation
to wash Mayim Acharonim still apply?
(a) The ROSH in Berachos (8:6), the RITVA, and other Rishonim write that in
addition to the danger of Sedomis-salt, there is another reason for washing
Mayim Acharonim. Before reciting the blessings of Birkas ha'Mazon, one
should wash out of sanctity, as the Gemara states in Berachos (53b).
Accordingly, even though we no longer have Sedomis-salt at our meals we
should wash Mayim Acharonim to sanctify ourselves before reciting Birkas
HALACHAH: The SHULCHAN ARUCH (OC 181:1) states "Mayim Acharonim is
obligatory." The MISHNAH BERURAH (181:1) mentions the reasoning of the Rosh
and the other Rishonim (a), that washing the hands is necessary in order to
sanctify and purify them before reciting Birkas ha'Mazon. The Mishnah
Berurah adds (from the Rambam) that even if the only reason for Mayim
Acharonim is so that we don't blind ourselves with Sedomis salt, one should
wash Mayim Acharonim since might have other salt that has the same
characteristics of Sedomis-salt.
(b) TOSFOS (DH Mayim Acharonim and in Berachos 53b, DH v'Hiyisem), however,
says that it is no longer the practice to wash Mayim Acharonim since (1) we
do not use Sedomis-salt and (2) it is not our practice to dip our fingers
into salt and taste a little after eating a meal. Washing Mayim Acharonim
was a measure of sanctity only when these two reasons existed, but not
(c) TOSFOS (in Berachos, ibid.) and the ROSH (ibid.) add mentions that even
if one rules that since we are not accustomed to washing our hands after
every meal and we do not consider our hands to be soiled, we do not need to
wash them for Birkas ha'Mazon, nevertheless, one who minds leaving his hands
slightly soiled from the meal *is* obligated to wash Mayim Acharonim for
Birkas ha'Mazon. For him, it is indeed a measure of sanctity to wash after
However, at the end of the Halachos of Mayim Acharonim, the SHULCHAN ARUCH
(181:10) cites the opinion of Tosfos (b) who says that the obligation of
Mayim Acharonim no longer applies. He adds, though, that one who always
washes his hands and is concerned about even a little dirt on his hands is
obligated to wash Mayim Acharonim before reciting Birkas ha'Mazon, as Tosfos
in Berachos (c) rules.
The MISHNAH BERURAH there (181:22) cites the VILNA GA'ON, MAGEN AVRAHAM,
MAHARSHAL, and BIRKEI YOSEF, all of whom strongly maintain that Mayim
Acharonim is still obligatory (even if one's hands are not dirty), like the
first opinion (a).
In practice, some follow the ruling of the Shulchan Aruch in OC 181:1, and
others follow the opinion of Tosfos as cited in Shulchan Aruch 181:10. Those
who maintain that Mayim Acharonim is obligatory should wash their entire
hands with at least a Revi'is of water on each hand (BI'UR HALACHAH 181:4,
DH Ad Perek; see also TESHUVOS V'HANHAGOS 1:173).
QUESTION: The Mishnah describes how the area around a well in Reshus
ha'Rabim can be enclosed in order to make it into a Reshus ha'Yachid to
permit drawing water from the well on Shabbos. Four corner pieces, each made
up of two perpendicular boards (which are each one Amah long and ten
Tefachim high), are placed at four corners around the well forming a frame
of a square area. This area is considered to be enclosed by virtue of the
corner boards which are viewed as forming Mechitzos around the area. The
space between the boards on each side can be up to 10 Amos according to
Rebbi Meir, or 13 1/3 Amos according to Rebbi Yehudah. A plank may be placed
in the open gap in order to increase the length of each side.
3) HALACHAH: "PASEI BIRA'OS" NOWADAYS
(a) How can this permit carrying the water into the enclosed area? The
Gemara said earlier (15b) that Hashem taught Moshe that in order to have a
properly enclosed Reshus ha'Rabim, the amount of breached area must not
exceed the amount of fenced area. Here, though, the amount of breached area
between the corner pieces is certainly more than the amount of fenced area
(the corner pieces themselves)!
(b) Similarly, there is a problem of "Asi Avira d'Hai Gisa v'Hai Gisa":
since the open airspace on each side of the plank in the middle is greater
than the width of the plank, the plank is viewed to be non-existent. Why,
then, is it permitted to extend the length of the Pasei Bira'os merely by
placing a plank of one Amah in the middle of each side?
(a) TOSFOS (DH Osin and DH v'Arba'ah) answers that Mid'Oraisa, any area
surrounded by one-Amah wide planks on each side is considered to be an
"entranceway," rather than a breach. Only when there are open breaches, do
we rule that the amount of breached area must not exceed the amount of
fenced area. Entranceways (i.e., areas with a full Tzuras ha'Pesach on the
d'Rabanan level, Eruvin 11a, or with a one Amah post on each side on a
d'Oraisa level), no matter how wide they may be, do not invalidate a
(b) "Asi Avira d'Hai Gisa" does not invalidate the corner pieces around the
well since it is only a Rabbinic invention. Mid'Oraisa, open spaces on each
side of a Mechitzah cannot invalidate it. (This certainly is the case when
the Mechitzah forms an entranceway, such as when there are one Amah wide
posts on either side of an open space.) For the benefit of the Olei Regalim
the Rabanan were lenient and they only necessitated satisfying the d'Oraisa
requirements. As long as the area inside the planks is a Reshus ha'Yachid
mid'Oraisa, they permitted drawing water for the animal and putting the
bucket of water between the planks for the animal to drink.
OPINIONS: The Rabanan permitted making a Mechitzah with the bare minimum
dimensions in order for the Olei Regalim to be able to feed their animals
from the public wells. Does this Halachah apply nowadays? Is it possible to
make an area into a Reshus ha'Yachid in such a manner?
(a) The Gemara (21a) explains that outside of Eretz Yisrael and Bavel it is
not permitted to use Pasei Bira'os because "there are not many Yeshivos" in
Chutz la'Aretz. Rashi explains that since there were not many Talmidim
traveling from one place to another to learn Torah, the Rabanan did not
permit erecting Pasei Bira'os. They only permitted Pasei Bira'os for the
Olei Regalim or those traveling for a Devar Mitzvah.
It would seem that Pasei Bira'os were not allowed in Chutz la'Aretz only
because there are no Yeshivos in Chutz la'Aretz. But if people *are* going
from Yeshiva to Yeshivah in Chutz la'Aretz, or to any other Devar Mitzvah,
it seems that it would be permitted to make Pasei Bira'os. This is indeed
the opinion of the RITVA, RASHBA, and OR ZARUA (cited by the Hagahos
(b) The RAMBAM, RIF, and ROSH do not mention any of the Halachos of Pasei
Bira'os. It seems that they rule that one may *not* make Pasei Bira'os
nowadays. When the Gemara says that it is not permitted in Chutz la'Aretz
because there are no Yeshivos there, it means that when the Rabanan
initially permitted the construction of Pasei Bira'os, they did not permit
it in Chutz la'Aretz because there were no people traveling to and from
Yeshivos. The original enactment did not apply to Chutz la'Aretz, and no
matter what happens in later times the Rabanan did not make a new enactment
to permit Pasei Bira'os outside of Eretz Yisrael. This also seems to be the
ruling of the SHULCHAN ARUCH, who omits all of the Halachos of Pasei