THOUGHTS ON THE DAILY DAF
brought to you by Kollel Iyun Hadaf of Har Nof
Rosh Kollel: Rav Mordecai Kornfeld
Ask A Question about the Daf
ERUVIN 31-35 - have been dedicated by Mrs. Rita Grunberger of Queens, N.Y.,
in loving memory of her late husband, Yitzchok Yakov ben Eliyahu Grunberger,
whose Yahrzeit is the 10th of Sivan.
1) BREAKING DOWN A WOODEN "MIGDAL" ON SHABBOS
QUESTION: According to Rabah and Rav Yosef, the Migdal of the Mishnah (34b)
is one made of wood. The Gemara at first suggests that the argument in the
Mishnah is whether this Migdal is considered a utensil ("Kli"), in which
case it is permitted to break down on Shabbos, or whether it is considered a
building ("Ohel"), in which case it is forbidden to break down on Shabbos
(because of "Soser Binyan").
What does the Gemara mean? If the Migdal has a capacity of forty Se'ah, it
is certainly an Ohel. If it does not hold forty Se'ah, it is certainly a
Kli. In what case could there be an argument whether it is considered an
Ohel or a Kli? What type of Migdal is the Mishnah discussing?
(a) TOSFOS RABEINU PERETZ explains that the Mishnah is discussing a Migdal
that holds forty Se'ah. However, since it is something that is often moved
around even when it is full, therefore there is an argument whether it is
considered an Ohel or a Kli. The Gemara then asks that there is no source
for creating such an argument; the discussion in Zavim is revolving in a
different point entirely.
(b) TOSFOS HA'ROSH and the RITVA also explain that the Mishnah is discussing
a vessel that holds forty Se'ah. However, they assert that such a Kli indeed
cannot be Mekabel Tum'ah. The opinion that says that it *can* become Tamei
is not talking about the vessel itself, but the Kelim that are inside of it.
If a Zav causes a vessel that is weak and easily shaken to vibrate, it is as
if the Zav directly shook the contents of that vessel, and they are Tamei.
That is why the Mishnah discusses *Heset* and not Maga. It is referring to
shaking the items inside the vessel by shaking the vessel, which is done by
Heset and not be Maga.
The Gemara assumes that the type of vessel that is so heavy that a Zav who
shakes it is not Metamei what is inside of it is not considered a vessel
(but rather an Ohel) with regard to Shabbos.
2) A "CHAZAKAH" DURING "BEIN HA'SHEMASHOS"
QUESTION: The Mishnah mentions a case of an Eruv made with Terumah food that
became Tamei, but it is uncertain whether the food became Tamei before
nightfall (in which case the Eruv would be invalid) or after nightfall (and
the Eruv is valid). Rebbi Meir and Rebbi Yosi argue whether such an
uncertain Eruv is valid or not. Rebbi Meir maintains that an Eruv in doubt
is *not* a valid Eruv. The Gemara asks how can Rebbi Meir be stringent
regarding an Eruv in doubt, when elsewhere we find that he is lenient in a
case of doubt (in a case where one is in doubt whether the body that one
touched at night was living or dead at the time that he touched it).
The Gemara answers that the case of the Eruv that became Tamei is when it is
known for sure that the Terumah became Tamei at the beginning of Bein
ha'Shemashos (that is, a Sheretz fell on it at that time).
If so, asks the Gemara, why does Rebbi Yosi say that the Eruv is valid? The
Gemara is forced to retract its suggestion that the case is when the Terumah
became Tamei at the beginning of Bein ha'Shemashos.
Why did the Gemara not suggest a simpler answer, asks REBBI AKIVA EIGER
(Gilyon ha'Shas). TOSFOS in Shabbos (34a, DH Sheneihem) explains that a
Chezkas Taharah is effective only in a case when one is not sure when an
item became Tamei (for example, before or after Bein ha'Shemashos). If,
however, it is known for certain that the item became Tamei during Bein
ha'Shemashos, but we are not sure whether Bein ha'Shemashos is day or night,
then we *cannot* use the Chazakah to determine that the item is Tahor until
the night. A Chazakah can only tell us that an item retains its status quo
until the latest possible moment (that is, until the moment at which there
is no longer any doubt about its status). Since, in the case of an item
becoming Tamei during Bein ha'Shemashos, we know *exactly when* the item
became Tamei, and the only doubt is whether that point in time was
considered day or night, the Chazakah does not tell us that it is day and
the food is Tahor.
If so, the Gemara should have said that Rebbi Meir will admit that the food
is Tamei in the case of the Mishnah because it is discussing a case where we
know that the Sheretz fell onto it during Bein ha'Shemashos, rendering it
Tamei. A Chazakah cannot tell us whether the given moment during Bein
ha'Shemashos when the Sheretz fell on the Terumah is day or night. In such a
case, Rebbi Yosi should still say that it is a valid Eruv because he
maintains that any Eruv in doubt is valid. Why did the Gemara not suggest
such a case?
(a) RASHI (Shabbos 34a) seems to disagree with Tosfos's rule. Rashi
maintains that a Chazakah could be applied even in such a case. Even though
we know exactly when the Sheretz fell on the Terumah, the Chazakah can tell
us that that moment during Bein ha'Shemashos was Halachically nighttime and
not daytime (and the Eruv is thus valid), since night is inherently later
than day. According to Rashi, then, the Gemara was not able to suggest that
this is the case in which Rebbi Meir and Rebbi Yosi argue, because in such a
case Rebbi Meir would agree that it is a valid Eruv because of the Chazakah.
(b) The RESHASH points out that from Berachos 2a it seems that Rebbi Meir
and Rebbi Yosi are of the opinion that the duration of Bein ha'Shemashos is
not more than "k'Heref Ayin," the blink of an eye. If so, it may be
suggested that we cannot be in doubt because the Sheretz fell during Bein
ha'Shemashos. If Bein ha'Shemashos is the length of the blink of an eye, the
Sheretz cannot fall exactly at that moment. That is why the Gemara cannot
say that the argument is when the Sheretz fell at exactly that moment.
(c) Perhaps when the Gemara says that there was a Sheretz on the Terumah at
the beginning of Bein ha'Shemashos, it means to say exactly what Rebbi Akiva
Eiger suggests that the Gemara should say. Furthermore, our Gemara is
probably the source for Tosfos suggestion that a Chazakah does not apply
when the it is known that the Sheretz fell on the Terumah during Bein
ha'Shemashos. Tosfos learned that the Gemara is suggesting that the argument
in our Mishnah involves Rebbi Akiva Eiger's case, when the Sheretz fell on
the Terumah at a known point during Bein ha'Shemashos. If this is the
Gemara's case, then why does the Gemara ask that Rebbi Yosi should agree
that the Eruv is not valid? Since Chazakah does not apply in this case,
there should remain a Safek (whether the moment at which the Sheretz fell on
the Terumah is considered day or night), and Rebbi Yosi rules that a Safek
Eruv is valid!
The RASHASH explains that Rebbi Yosi indeed would not permit a Safek Eruv in
such a case. The Gemara concludes (36a) that according to Rebbi Yosi an Eruv
in doubt is valid only because of a Chazakah. (This is also clear from
Tosfos, ibid., DH Sheneihem). Without a Chazakah, Rebbi Yosi would not
permit use of the Eruv; therefore the case of the Mishnah cannot be that a
Sheretz fell on the Terumah during a known point of Bein ha'Shemashos.