THOUGHTS ON THE DAILY DAF
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Rosh Kollel: Rav Mordecai Kornfeld
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SUKAH 21-25 - my brother Ari Kornfeld has generously sponsored one month of
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1) SECHACH PLACED ON THE LEGS OF A BED: NOT "KEVA"
OPINIONS: In the Mishnah, the Tana Kama and Rebbi Yehudah argue about a
Sukah that was made by placing Sechach on the legs of a bed. The Tana Kama
says that such a Sukah is valid, and Rebbi Yehudah says that it is invalid.
Two reasons are given in the Gemara for Rebbi Yehudah's opinion. One Amora
says that his reason for invalidating the Sukah is because it is not "Keva."
The other Amora says that his reason is because something which is Mekabel
Tum'ah is supporting the Sechach, and such a Sukah is invalid (see next
Insight). What does the Gemara mean when it says that this Sukah is not
2) SECHACH PLACED ON THE LEGS OF A BED: NOT "MA'AMID"
(a) RASHI explains that since the bed poles are supporting the Sukah,
whenever one moves the bed the Sukah will move, and a movable Sukah is not a
"Diras Keva." Since Rebbi Yehudah requires that a Sukah be a "Diras Keva"
(7b), he invalidates this Sukah.
However, the Mishnah later (22b, also cited on 7b), which says that a Sukah
may be made on top of a wagon or camel, implies that a movable Sukah is
valid! Rashi will have to say that Rebbi Yehudah argues with that Halachah,
just like Raban Gamliel argues with it (TOSFOS DH sh'Ein Lah). However,
regarding a Sukah built on top of a boat, which is also mentioned in that
Mishnah, perhaps even Rebbi Yehudah agrees that it is valid (if it is a
strong Sukah) because it is not considered to be moving. Since a boat rests
on the water and the water moves under it, it is considered to be "Keva"
According to this, we should not rule like Rebbi Yehudah in this case, and
the Sukah made by placing Sechach on the legs of a bed should be valid,
because this is how we rule in the case of a Sukah on top of a wagon.
The RAN gives a different answer. In the case of a Sukah on the legs of a
bed, the floor of the Sukah is the ground beneath the bed; the Sechach is
merely being supported by the bed's poles. In that case, when the bed is
moved, the Sechach is moved to cover an entirely different floor. A Sukah
built on a wagon, on the other hand, has as its floor the floor of the
wagon, and thus as the wagon is moved, the Sukah's floor moves with it.
Therefore, even though we rule that a Sukah on a wagon is valid, we could
also rule like Rebbi Yehudah in the case of a Sukah on a bed.
According to this explanation of the Ran, when the Gemara concludes that the
Sukah is valid if one placed the Sechach over the bed (without supporting it
on the legs of the bed), it means that one put the Sechach on the bed in
such a way that the bed is the floor of the Sukah, and thus when the bed
moves, the floor of the Sukah also moves.
(b) TOSFOS and the RAMBAN, quoting the Yerushalmi, explain that "Keva" means
that it is not a Dirah in which it is easy to live, because there are not
ten Tefachim from the top of the bed until the roof of the Sukah. Therefore,
it is not a Dirah which can be used in a normal way, which is what "Keva"
(c) The RA'AVAD on the Rif explains that the Sukah was not on the bed
itself, but the bed was supporting the Sukah on one side. When one moves the
bed to sleep in it, the whole Sukah will tumble down. Therefore, it is like
a Sukah which cannot stand up to a Ru'ach Metzuyah (that is, normal usage
will cause it to fall down), and such a Sukah is invalid (even according to
those who allow a Sukah which is a Diras Ara'I, Daf 22a).
QUESTIONS: Rebbi Yehudah maintains that a Sukah that was made by placing
Sechach on the legs of a bed is invalid. Two reasons are given in the Gemara
for Rebbi Yehudah's opinion. One Amora says that his reason for invalidating
the Sukah is because it is not "Keva" (see previous Insight). The other
opinion says that his reason is because something which is Mekabel Tum'ah is
supporting the Sechach, and such a Sukah is invalid. RASHI explains that the
object which serves to support ("Ma'amid") the Sechach is considered like
the Sechach itself, and thus if it is Mekabel Tum'ah it is Pasul, just like
Sechach itself which is Mekabel Tum'ah. However, there seem to be several
sources which contradict this principle.
3) HALACHAH: "MA'AMID" AND "MA'AMID D'MA'AMID"
(a) Rava (15b) discussed placing Sechach on metal rods. He said that if the
Sechach is placed across the rods, the Sukah is valid, even though they are
supported by the rods. Why is the Sukah valid? It should be invalid because
the Sechach is being supported by a Ma'amid which is Mekabel Tum'ah!
(b) The Mishnah (22b) says that a Sukah built atop a tree is valid. Why is
it valid? It is being supported by the tree, which is attached to the
ground, and anything that is attached to the ground is Pasul as Sechach.
Thus, a Ma'amid which is attached to the ground should invalidate the Sukah
(c) Common practice is to allow Sechach to be supported by a solid wall
(made of dirt/cement). Dirt (or rock) is not valid for use as Sechach (as
the RITVA states on 4a, 11b, and at the end of 21b). If so, how can it be
permitted to be used as a Ma'amid?
(a) As for the question from the Rava's opinion that Sechach may be rested
on metal rods, it must be that Rava maintained that Rebbi Yehudah's reason
in the Mishnah here is because a Sukah built on top of the legs of a bed is
not "Keva." Rava does not agree with the reason that the Ma'amid is Mekabel
Tum'ah, and therefore he permits the Sechach to be supported on an object
which is Mekabel Tum'ah. (KORBAN NESANEL)
(b) Regarding a Sukah in a tree, the RA'AVAD answers that the Pesul of
supporting Sechach on a Ma'amid which is Mekabel Tum'ah is only a Pesul
mid'Rabanan. The Rabanan enacted a Gezeirah to prevent people from thinking
that just as an object which is Mekabel Tum'ah may be used as a Ma'amid, so,
too, it may be used as the Sechach itself. However, building a Sukah in a
tree is an uncommon practice, and the Rabanan did not apply their Gezeirah
in an uncommon case.
The RAMBAN and RITVA answer that even if the Pesul of being Ma'amid with
something that is Mekabel Tum'ah is a Pesul mid'Oraisa, as Rashi says
("Ma'amid is considered like Sechach"), it could be that the Mishnah that
mentions the Sukah in the tree is referring to Sechach that was supported on
top of boards, and those boards were resting on the tree. The tree itself is
not directly supporting the Sechach, but only it is only supporting the
boards which are supporting the Sechach. The tree, then, is a Ma'amid of a
Ma'amid (Ritva), and therefore it is no worse than every other Sukah which
is ultimately being supported by the ground (which cannot be used for
(c) A solid wall (made of dirt) may be used for supporting a Sukah. The RAN
suggests some logical basis for this practice. First, it is very uncommon
for someone to use dirt (or stone) for the Sechach of a Sukah, and therefore
the Ra'avad's reasoning (see (b) above) applies here too.
Second, the Ran and Ritva explain that everyone knows that dirt cannot be
used for Sechach, because a roof made of dirt is the roof of a house and not
of a Sukah. Since everyone knows, there is no Gezeirah that people will
confuse the Ma'amid with the Sechach. (This again explains the practice only
according to the Ra'avad, who says that the Isur of Ma'amid is mid'Rabanan,
but not according to Rashi who says that it is mid'Oraisa.)
OPINIONS: According to one reason given for the opinion of Rebbi Yehudah, an
item which can be Mekabel Tum'ah (or is otherwise invalid for use a Sechach)
may not be used to support the Sechach. This issue is very relevant in
practice. Is it permitted to use metal rods to support the Sechach of one's
Sukah? Likewise, may one use nails to hold down the boards which support the
Sechach? What is the Halachah?
(a) In the Mishnah, the Rabanan argue with Rebbi Yehudah. The BA'AL HA'ME'OR
says that the Halachah follows the Rabanan. His reasoning is apparently
either because they are the majority opinion, or because we find that the
Mishnah later (22b) permits placing Sechach on a portable object and on an
object which is invalid to be used as Sechach (as the Ra'avad explains the
intention of the Me'or).
HALACHAH: The SHA'AR HA'TZIYON (630:60) lists many Rishonim who do not put
limits on the type of Ma'amid used to support the Sechach. Therefore, he
says that although it is good to be stringent l'Chatchilah, b'Di'eved the
Sukah is certainly valid even with a Ma'amid that is Mekabel Tu'mah.
The other Rishonim say that since the Amora'im are discussing the reason of
Rebbi Yehudah, the Halachah follows his opinion, and thus a Sukah built by
placing Sechach on the legs of a bed is invalid. (According to the ROSH, the
Rabanan and Rebbi Yehudah do not even argue; Rebbi Yehudah is explaining the
opinion of the Rabanan.) However, two reasons were given for Rebbi Yehudah's
opinion. The ROSH says that the primary reason is because such a Sukah is
not "Keva." He accepts the explanation for "Keva" of the Yerushalmi cited by
Tosfos and the Ramban (see Insight #1:b); Rebbi Yehudah disqualifies the
Sukah because it's Sechach is too low (it is less than ten Tefachim from the
top of the bed) and thus it is not "Keva." This is how the SHULCHAN ARUCH
(OC 630:3) rules.
However, the RAMBAN, RITVA, and RAN rule stringently that the other reason,
that one may not support Sechach with an item which is Mekabel Tum'ah, is
also accepted l'Halachah. The Shulchan Aruch (629:7) indeed mentions that it
is questionable whether one may use a Ma'amid that is Mekabel Tum'ah. (Some,
however, explain this Halachah in the Shulchan Aruch differently, and assert
that the Shulchan Aruch rules elsewhere -- OC 628 -- leniently, that rods,
which are Mekabel Tum'ah, may be used as a Ma'amid.)
What is the Halachah concerning a Ma'amid of a Ma'amid (that is, the item
supporting the Sechach is something which is valid for Sechach, but the item
supporting that Ma'amid is *not* valid for Sechach)? The MAGEN AVRAHAM and
the VILNA GA'ON, commenting on the Shulchan Aruch (629:8), say that a
Ma'amid of a Ma'amid is permissible even though it is Mekabel Tum'ah. The
proof is that the Ramban, Ritva, and Ran -- who say that one should be
stringent when it comes to a Ma'amid -- explain that if one supports the
Sechach on wooden poles that are being supported by a bed, the Sukah is
valid even though the bed is Mekabel Tum'ah and is supporting the Ma'amid
(that is, the bed is a Ma'amid of a Ma'amid).
The CHAZON ISH (143:2), however, is stringent, because the Ramban permits
such a case of a Ma'amid of a Ma'amid only because the Ma'amid (which is
invalid as Sechach) is a horizontal surface that is serving the same purpose
as the ground ("Ma'aseh Karka b'Alma"). That is only permitted, though, if
the Pasul item is the floor of the Sukah. If the item is standing upright
and supporting the Ma'amid of the Sechach, such as nails holding down the
support beam of the Sechach, then that logic will not permit using a Ma'amid
of a Ma'amid that is invalid for Sechach. (The RITVA seems to present the
arguments of the Ramban slightly differently, saying that the Heter of
Ma'amid of a Ma'amid is because the secondary Ma'amid is further away from
the Sechach, and not because it is merely serving as the ground of the
Sukah. It could be, then, that this proof of the Chazon Ish is actually a
Machlokes Rishonim between the Ramban and Ritva.)
The Chazon Ish presents a second argument. He says that if the Ma'amid (even
one which may be used as Sechach) of the Sechach rests on something which is
Mekabel Tum'ah, then that Ma'amid can no longer be used as Sechach. If so,
the Sechach resting on that Ma'amid is resting on something which cannot be
used as Sechach (a chain reaction), and thus the Sukah should be invalid.
However, it could be that this logic does not apply here to forbid a Ma'amid
of a Ma'amid. These Rishonim (Ramban, Ritva, Ran) hold that using a Ma'amid
which is Mekabel Tum'ah only invalidates the Sukah mid'Rabanan, due to a
Gezeirah that one might err and think that it is permitted to use such
material for the actual Sechach of the Sukah. Since it is only a Gezeirah
d'Rabanan, the Rabanan limited their Gezeirah to an actual Ma'amid, and were
not concerned for the logic of a secondary Ma'amid.
The Chazon Ish concludes that one should be careful not to use even a
Ma'amid of a Ma'amid that is Mekabel Tu'mah (except for the cases mentioned
in the previous Insight, where it is permitted to use Sechach Pasul as a
Ma'amid according to all opinions). As mentioned earlier, the Sha'ar
ha'Tziyon says that b'Di'eved the Sukah is valid.