ANSWERS TO REVIEW QUESTIONS
prepared by Rabbi Eliezer Chrysler
Kollel Iyun Hadaf, Jerusalem
Previous dafEruvin 79
(a) Rebbi Yossi says that straw which one has specifically in mind not to
move away is like S'tam earth and is Batel; and earth which he
specifically has in mind not to move away, is like S'tam straw, which is
not Batel (in other words, S'tam earth is Batel, but S'tam straw is not).
In that case, why should the Mishnah in Ohalos go like Rebbi Yossi, and
not our Mishnah?
A ledge of even a Mashehu which runs along the length of the ditch which
is exactly four Tefachim wide will suffice to combine the two courtyards
(since the ditch is no longer four Tefachim wide).
(b) Consequently, Rav Asi learns that S'tam Tana in Eruvin is Rebbi Yossi,
in which case our Tana will conform with the Mishnah in Ohalos, both of
which go like Rebbi Yossi.
(c) Rav Huna Brei de'Rav Yehoshua differentiates between Tum'ah and
Shabbos - Tum'ah requires permanent Bitul, and unless we know that the
owner was Mevatel, it is not Batel; whereas Shabbos, anything that is
Muktzah (such as earth, or even a purse) the owner will be Mevatel there,
even though it is only for one day (straw etc., is not Muktzah, since it
is fit to feed his animals).
(d) The Mishnah in Ohalos, answers Rav Ashi, is speaking about a house,
which does not stand to be filled in with straw or with anything else.
Consequently, the Tana contends that Stam is not Batel; whereas in our
Mishnah, which speaks about a ditch, which does stand to be filled in, the
Tana maintains that Stam it is not Batel.
A plank that combines two protruding ledges from the upper floor of two
adjacent houses will not be effective - either if one of the houses
protrudes into the street more than the other one (since the plank is
placed diagonally, and not at ninety degrees); or if one of the ledges is
more than three Tefachim higher that the other?
(a) The residents of the two courtyards will be forced to stop feeding
their animals from the hay-stack - as soon as the hay decreases to a
height of less than ten Tefachim to a length of more than Amos.
(b) We not worried that this may happen without them realizing it -
because we are talking about a lot of hay, and it is unlikely that the
animals will devour so much straw in the course of one day.
(c) For the reason mentioned in the previous question, Rav Huna forbade
the residents to take straw in boxes to feed their animals. He may
however, have forbidden them to do so because, since the straw was
designated for the Mechitzah, he considered it Muktzah. (See Rosh, Si'man
6, who queries both of Rashi's explanations, and establishes our Sugya by
(a) One is ...
1. ... permitted to place one's animal on top of growing grass on Shabbos
- because, due to the fact that the Isur of detaching grass on Shabbos is
d'Oraysa, the Jew is unlikely to pluck it for his animal; whereas ...
(b) Rav HUna permits him to feed his animal by standing in front of his
animal at a slight distance from the straw, thereby coaxing it to walk to
the pile of straw and eat.
2. ... not however permitted, to place one's animal on top of a detached
pile of hay. Here, since the Isur of feeding one's animal involves no more
than Muktzah, we suspect that the owner may be tempted to pick up some
straw in order to feed his animal.
(c) The Beraisa permits them to take straw in boxes from the haystack
which is in the barn - because the fact that the barn has walls makes it
easier to realize when the hay-stack in the middle has reached a level of
less than ten Tefachim (and this will apply even to Rashi's second
explanation of Muktzah - in 4c - because as long as the wall is higher
than ten Tefachim, the straw is not really Muktzah, because it is not
needed for the Mechitzah).
(a) If the hay in the barn dropped to a level of less than ten Tefachim
for a distance of more than ten Amos - then they are only permitted to
make a combimed Eruv, but not endependent ones.
(b) To reconcile our Beraisa, which implies that, as long as the straw is
ten Tefachim high, the hay-stack is considered a Mechitzah, on those who
hold (above 72a) that a case such as this (see Tosfos DH 'Shema Minah'),
the walls must reach the ceiling in order for them to qualify as Mechitzos
- Abaye establishes the Beraisa by walls that are a fraction under
thirteen Tefachim high, in which case the ten Tefachim walls will indeed
be considered as if they reached the ceiling, because of 'Levud'.
(c) Rav Huna, who forbids the owners to take hay from the hay-stack to
feed their animals, establishes the Beraisa (which expressly permits them
to take hay on Yom-Tov from a barn which divides between two Techumei
Shabbos) when the walls are exactly ten Tefachim high - in which case a
hay-stack of anything more than seven Tefachim will constitute a Mechitzah
(because of 'Levud').
(d) When the Beraisa says 'Nisma'et ha'Teven me'Asarah' - it means to say
mi'Toras Asarah' (and if a Mechitzah reaches within three Tefachim of
where it is supposed to, the seven plus hay-stack is considered as if it
was ten Tefachim, and reached the ceiling).
(a) When the Beraisa says 'Nisma'et ha'Teven me'Asarah Tefachim, Sheneihem
Asurin', who said that the straw diminished to less than Tefachim on
Shabbos? Maybe that had happened already on Friday, and the 'new'
residents forbid because they failed to make an Eruv then.
(b) According to the Gemara's second explanation - both Bitul Reshus and
locking the door are necessary, because, since he is used to carrying in
the Chatzer, we are afraid that he will continue to do so. In fact, this
applies to every Mevatel Reshus (i.e. that the one who is Mevatel his
Reshus must lock his door). Note: This Chumra is restricted to the first
Shabbos only - Tosfos DH 've'Iba'is Eima'. In addition, it does not mean
that he cannot use the door, but that, when it is not in use, he must keep
it locked - Rosh Si'man 7.
(c) 'Hu Asur, va'Chavero Mutar' speaks even if his friend was then Mevatel
his Reshus back to him - to teach us 'Ein Mevatlin ve'Chozrin u'Mevatlin'.
(d) The Chidush of 've'Chen Ata Omer be'Guv shel Teven she'Bein Shenei
Techumei Shabbos' - is that even according to Rebbi Akiva, who holds that
Techumin d'Oraysa, the residents on both sides of the Techum are permitted
to take from the straw in the middle, and we are not worried that they
might mistakenly take from each other's straw, which is an Isur d'Oraysa;
whereas Eruv Chatzeros is only an Isur de'Rabbanan - even according to
(a) Someone places his own food (for a Shituf Mavu'os) in one of the
Chatzeros on behalf of his co-residents, says - 'Harei Zu le'Chol B'nei
(b) One's small children (or possibly even grown-up children who are still
eating at their father's table - see Tosfos DH 'u'Mezakeh'), and one's
non-Jewish slave are not eligible to act as agents to place the Shituf on
behalf of the Mavoy.
(c) The Sheli'ach must lift the barrel with the food one Teach from the
ground - in order to be acquire it on their behalf.
(a) The Sabi de'Pumbedisa - were Rav Yehudah and the Talmidim of his
Yeshivah. Besides the previous Halachah, they also said - that the person
who recites Kidush is obligated to drink a cheekful of wine in order to
fulfill one's obligation.
Shmuel defines an unspecified Asheirah as one - whose fruit they
specifically designated for their celebrations during their idolatrous
(b) The Heter of making a fire on Shabbos for a woman who gave birth -
does extend to other sick people as well, since we learnt in the name of
Shmuel that if someone who let blood is feeling cold, it is permitted to
light a fire for him ...
(c) ... even in the middle of summer.