ANSWERS TO REVIEW QUESTIONS
prepared by Rabbi Eliezer Chrysler
Kollel Iyun Hadaf, Jerusalem
Previous dafEruvin 49
ERUVIN 49 & 50 - have been dedicated jointly by the Feldman family to the
memory of Hagaon Rav Yisroel Zev [ben Avrohom Tzvi] Gustman Ztz"l (Vilna-
(a) If a courtyard which opens into two Mavu'os ...
1. ...did *not* make an Eruv with them - then neither of the courtyards
that flank the courtyard on the other side is permitted to carry objects
into the Mavoy (assuming that the residents of the courtyard tend to use
(b) In the former case, where the Chatzer did not make an Eruv with both
Mavu'os (but only with one of them), the residents that Mavoy will be
permitted to carry into the Mavoy - provided the members of the courtyard
do not tend to use the other Mavoy.
2. ... *did* make an Eruv with both Mavu'os - then *they* are permitted to
carry into it, but not vice-versa (like Shmuel just said above).
(c) The residents of the Mavoy through which the residents of the
courtyard *are* accustomed to walk, are permitted to carry in their own
courtyard, in spite of the fact that they did not make an Eruv together -
if the residents of the other Mavoy made an Eruv with the Chatzer, since
the Mavoy which had been accustomed etc., did not join in the Eruv.
(d) If the Mavoy which the residents of the one Chatzer tended to use made
its own Eruv, but neither the Chatzer nor the second Mavoy did likewise -
then, to ensure that the members of the Chatzer do not forbid the members
of the Mavoy to carry, in spite of their Eruv, we force the members of the
Chatzer to use the other Mavoy - because of 'Kofin Oso Al Midas Sedom'
(since it makes absolutely *no* difference to them which Mavoy they use,
though it *does* make a difference to the residents of the Mavoy which
made an Eruv.
(a) Shmuel invalidate the Eruv of someone who is fussy that his bread
should not be eaten by any of the participants - because such an attitude
negates the whole purpose of an Eruv, which is to combine the various
parties concerned (as the very word 'Eruv' suggests).
(b) The men of Vardina were known for their stinginess.
(c) Beis Hillel only validates an Eruv that is placed in two receptacles -
when this is due to the one receptacle being full. If however, the Eruv is
*deliberately* divided into two receptacles, it is Pasul - because here
too, it negates the concept of merging, which is the essence of Eruv.
(a) Although both the person who is fussy about his Eruv being eaten, and
someone who is fussy about placing *his* Eruv in the same receptacle as
the others' - negate the concept of combining, they do so in different
ways; the one does not want his Eruv to be eaten, but does not care where
it is placed, whilst the other one is just the opposite, so perhaps we
would not learn one from the other. Therefore Shmuel needed to tell us
(b) When Shmuel exempts the person in whose house the Eruv (bread that was
collected from each of the participants) is placed, from placing his bread
- he exempts him altogether from the need to place bread, since his house
has been designated for the Eruv, it is as if everyone in that courtyard
was living there, so why should he need to place bread?
(c) The Gemara initially thought - that Shmuel was exempting him from
placing his bread together with the others, because, wherever the bread is
lying, it will combine with the other loaves (from which we would have
inferred that all the bread does not need to be placed in the same
(a) Shmuel holds 'Eruv Mishum Kinyan'. Nevertheless, in his opinion, money
may not be used - because people will think that one is obligated to use
money, and refrain from making an Eruv (which is only permitted for a
D'var Mitzvah), even when they have bread.
(b) Rabah holds that 'Eruv Mishum Dirah' - because people's minds are on
their bread, and where their bread is, that is where they are domicile. It
is as if that was the only house in the Chatzer.
(c) 'Me'arvin bi'Ch'li' means - that instead of using bread, one may use
any object which serves to acquire the Reshus of the person who gives his
house for this purpose.
(d) The other two differences between the two reasons - is if the bread is
(more than enough for two meals, but) less valuable than a Shaveh Perutah,
or whether a Katan can acquire the Eruv on behalf of any of the residents:
If 'Eruv Mishum Kinyan', then it will *not* be valid, in either case;
whereas if 'Eruv Mishum Dirah', then it *will*.
(a) The Eruv does not acquire only on *his* own behalf (according to
Shmuel) - nor does only *he* become a resident (according to Rabah) -
because the fact of the matter is, that he was acting on behalf of them
all, and we apply the principle 'Shelucho shel Adam Kamoso' (nor is it
clear why the Gemara thought that this was not the case).
(b) The Gemara rules like Rebbi Shimon - that if the middle Chatzer made
an Eruv with the two outer ones, they are permitted to carry in the middle
Chatzer, and vice-versa (like Rav on 48b).
(a) A traveler who is approaching town, and who wants to be Koneh Shevisah
anywhere up to two thousand Amos ahead of where he is - can designate any
landmark that he is aware of (a tree or a wall) within that space - even
though he cannot actually see it - as his residence. Subsequently, he will
be able to walk two thousand Amos from there.
(b) He then measures his two thousand Amos ...
1. ... in a circle from where he is standing - according to Rebbi Chanina
(c) According to Rebbi Yehudah, Chazal instituted the concept of an Eruv
using bread - for the benefit of the rich man, to save him from having to
walk from his house to the border to wait for the entry of Shabbos; an
Eruv with bread enables him to send a Sheli'ach.
2. ... the Chachamim in the form of a square - according to the Chachamim
(because according to them, he always gains the corners - the quarter that
a square is more than a circle).
(d) According to Rebbi Meir, they instituted the concept of Eruv on foot -
for the benefit of the traveler, who has no bread with him.
(a) According to Rav, when Rebbi Meir in our Mishnah says 'Lo Amar K'lum,
he means nothing at all, not even four Amos - since, due to the fact that
the spot that he designated is not clear-cut, he does not acquire it as
his place of residence; on the other hand, he relinquished the spot where
he was standing when Shabbos entered. As a result, he ends up with neither
the one nor the other.
Rashi's second interpretation of 'Lo Amar K'lum', according to Shmuel - is
that he cannot walk two thousand Amos from the far side of the tree to his
house. He may however, walk the two thousand Amos between where he is and
the tree, because one way or another, he is Koneh Shevisah, either where
he is, or by the three. However, since we do not know which one, we are
strict, permitting only the area which incorporates both.
(b) According to Shmuel, 'Lo Amar K'lum' - means to grant him the right to
go the full two thousand Amos from the *far end* of his new Techum - where
his house is situated (because since the four Amos that he designated are
unspecified, we reckon the spot that he designated to be the *first* four
Amos at the *near end* of the tree, whereas his house is two thousand Amos
from the *far end*.
(c) When Shmuel says 've'Na'aseh Tachtav shel Ilan Chamar Gamal' - he
means that, on the one hand, we reckon his four Amos from the nearest
point of the tree (as we just explained in b.); and on the other, that,
when it comes to going two thousand Amos in the opposite direction (the
one from which he came), we reckon his four Amos from the furthest point
of the tree, thereby minimizing his two thousand Amos in *that* direction.
In fact, we go strict both ways.
(a) The Gemara does not probe Shmuel's reason for Rebbi Meir - because it
is obvious. In his opinion, Rebbi Meir holds (according to Rashi's first
explanation) that he is definitely Koneh Shevisah under the tree, only we
don't know at which point.
(b) Rav's reason is - either because one cannot be Koneh Shevisah by a
point which is not clear-cut; or because - 'Kol she'Eino be'Zeh Achar Zeh,
Af be'Bas Achas Eino' (Any two things which cannot become effective in
succession, cannot become effective simultaneously either).
Here, since he did not clarify *which* four Amos under the tree he was
designating, what he was in fact saying, was that all eight Amos under the
tree should be Koneh Shevisah. And that remains totally ineffective, since
he cannot acquire first one of the four Amos, and then the other.
(c) If he were to specifically designate four Amos out of eight - he would
still not be Koneh Shevisah according to the first reason (since the four
Amoswould still not be clear-cut); whereas, according to the second reason
- he would be Koneh Shevisah, since this is not a case of 'Bas Achas'.