OUTLINES OF HALACHOS FROM THE DAF
Prepared by Rabbi P. Feldman
of Kollel Iyun Hadaf, Yerushalayim
BAVA BASRA 66 - May the merit of learning and teaching Torah through D.A.F. to an audience of thousands worldwide bring Hatzlachah and Siyata di'Shemaya to Libi Feinberg and her family.
1) THE PESUL OF MAYIM SHE'UVIM IS MID'RABANAN
1. 65b (Beraisa): If a pipe was hollowed out and then
attached (it is considered a Keli), (so) it
disqualifies a Mikveh. (If three Lugim of water from
it fall into a Mikveh with less than 40 Se'ah of
water, the Mikveh is disqualified even when it will
have enough water)l
2. If it was attached and then hollowed out, it does
not disqualify a Mikveh. (It is not considered a
3. Question: This is unlike R. Eliezer, and unlike
i. (Mishnah - R. Eliezer): If a baker's board was
fixed into the wall, it cannot become Tamei;
4. Answer #1: The Beraisa is R. Eliezer. He is more
lenient about the board, for Tum'ah of wooden Kelim
without a receptacle is only mid'Rabanan.
ii. Chachamim say, it can become Tamei.
iii. R. Eliezer considers attached Kelim like land,
even if they were made and later attached.
Chachamim consider attached Kelim like
Metaltelim, even if they were made after they
5. Objection: This implies that Mayim She'uvim (water
that was in a Keli) disqualifies a Mikveh
mid'Oraisa. We hold that it is a Pesul mid'Rabanan!
6. Answer #2: Really, the Beraisa is Chachamim. They
are lenient about the pipe because Mayim She'uvim
disqualifies a Mikveh only mid'Rabanan.
i. If it was hollowed out and then attached they
are stringent, for it was a Keli before it was
1. Rif (Shevu'os 5b): Three Lugim of She'uvim
disqualify an incomplete Mikveh. One may add
She'uvim to a complete Mikveh, or to an incomplete
Mikveh through Hamshachah (pouring on the ground,
and it flows into the Mikveh).
2. Rambam (Hilchos Mikva'os 4:1,2): Mid'Oraisa one may
be Tovel in "Mikve Mayim" of 40 Sa'im, whether or
not it is She'uvim. Mid'Rabanan, Mayim She'uvim is
Pasul for Tevilah. Further, three Lugim of She'uvim
disqualifies a Mikveh. Even though it is
mid'Rabanan, it is learned from a Hekesh. "Ach Mayan
u'Vor Mikve Mayim Yihyeh Tahor" - Mikveh is written
between a spring, which is totally natural, and a
pit, which is filled totally by man. A Mikveh may
not be totally Mayim She'uvim like a pit, nor must
it be totally natural like a spring.
3. Rosh (Mikva'os 1): R. Tam says that it is a
tradition from Sinai that three Lugim of She'uvim
disqualify a Mikveh at the beginning. If three Lugim
of She'uvim fall into an incomplete Mikveh, they
disqualify it mid'Rabanan. He learns from R.
Eliezer's law, that if the first Revi'is of water in
a Mikveh was She'uvim, it disqualifies it. If three
Lugim of Mayim She'uvim fall into an incomplete
Mikveh, they disqualify it. Surely, he is more
stringent about Mayim She'uvim at the beginning
because it is mid'Oraisa!
i. Rejection (Rosh citing the Ri): No, R. Eliezer
is more stringent about Mayim She'uvim at the
beginning because it is a full Pasul Mikveh. A
Revi'is is the Shi'ur Mikveh for Tevilas Kelim.
We never find a tradition from Sinai about
Mayim She'uvim. Even if we did, sometimes we
say so about a mid'Rabanan law that is as clear
as a tradition from Sinai.
4. Rashbam (66a DH u'Masmah, according to Rashash):
Mid'Oraisa, a Mikveh must begin with (40 Sa'im of)
water that is not She'uvim. If Mayim She'uvim falls
in later, it is Batel. Yevamos 82b teaches that if a
majority of She'uvim falls in, it disqualifies
5. Tosfos (66a DH Michlal): The Rashbam and R. Tam say
that if the entire Mikveh is Mayim She'uvim it is
i. Source #1 (Toras Kohanim Shemini Parashah 9:1):
Had it said 'Mikve Mayim Yihyeh Tahor', we
would have thought that one may pour water to
make a Mikveh. Therefore, it says "Mayan (u'Vor
Mikve Mayim...)" to teach that a Mikveh must be
like a spring, i.e. it is totally bi'Yedei
6. Tosfos (ibid.): The Ri says that even if the entire
Mikveh is Mayim She'uvim it is Pasul only
ii. Rejection (Tosfos ibid.): Perhaps this is only
7. Source #1 (Tosefta Mikva'os 2:1): If one left a
Mikveh empty and later found it full, it is Kosher,
for this is a Safek about Mayim She'uvim. Surely, we
are lenient about the Safek because even all Mayim
She'uvim is Pasul only mid'Rabanan!
i. Suggestion: Perhaps initially there was water
inside that was not She'uvim.
8. Rejection: It does not say that the Mikveh was
lacking, rather, that it was empty!
i. Rebuttal (and counter-proof - Rashba in Tosfos
ibid.): The Tosefta says that the Mikveh is
Kosher because the Chazakah is that Mikva'os
are Kesherim, i.e. people make Mikva'os for
Tevilah, so we may assume that it was not
filled with She'uvim. If all Mayim She'uvim was
Pasul mid'Rabanan, we would be lenient even
without the Chazakah!
9. Source #2 (for Ri - Pesachim 17b): Liquids (water)
of Beis Mitbechai (the place where Korbanos are
rinsed) in Kelim are Temei'im. If they are in the
ground, they are Tehorim. In the ground is Tahor
only if there is a Revi'is, for [mid'Oraisa] it is a
valid Mikveh to be Tovel small Kelim.
ii. Support #1 (Seifa of the Tosefta): If there is
a Keli near where water flows from a pipe
(which is not a Keli) into a Mikveh, and we are
unsure whether the water went directly from the
pipe or if it went through the Keli, the Mikveh
is Pasul, for the Pesul (the Keli) is evident.
If the majority was Kosher water, the Mikveh is
iii. Rashba: We are stringent when it is possible
that the majority was She'uvim for this is
iv. Support #2 (Tosefta Mikva'os 2:5): If there
were two Mikva'os, one Kosher and one of
She'uvim, and one does not know in which he was
Tovel from Tum'ah mid'Oraisa and he touched
Taharos, they are Safek Temei'im.
v. Rashba: We are stringent because it is a Safek
i. The Gemara is Metaher even Mayim She'uvim, for
it contrasts water in the ground to water in
Kelim. Also, Stam liquids of Beis Mitbechai are
10. Rejection #1 (Rashba in Tosfos ibid.): Indeed, the
Tosefta discusses only liquids that are now in the
ground; it is Metamei if they were once in Kelim,
and is Metaher if they were never in Kelim.
11. Rejection #2 (R. Moshe of Pontiza in Tosfos ibid.):
Even though Mayim She'uvim disqualifies a Mikveh
mid'Oraisa, water in the ground is Tahor because
this was through Hamshachah, i.e. when water falls
on level ground it spreads out. A Mikveh made
totally from Mayim She'uvim via Hamshachah is Kosher
12. Question: Only the minority may be from Mayim
She'uvim via Hamshachah (Temurah 12a)!
13. Answer: That is mid'Rabanan.
14. Question: If a Mikveh of all Mayim She'uvim is Pasul
mid'Oraisa, we understand why three Lugim are Posel
mid'Rabanan. People used to Tovel in stinking water
in caves. Afterwards, they would pour three Lugim of
She'uvim on their heads. People used to say that the
Mikveh is not Metaher, only the Mayim She'uvim are
(Shabbos 14a), so Chachamim decreed that three Lugim
are Posel. However, if all She'uvim is Kosher
mid'Oraisa, why is there any decree about Mayim
15. Answer: It is a decree lest people immerse in a
Keli. The Torah requires a Mikveh resembling a
spring, i.e. in the ground.
1. Shulchan Aruch (YD 201:3): The 40 Sa'im of a Mikveh
may not be She'uvim. If they are, it is Pasul.
2. Rema: If the entire Mikveh is She'uvim it is Pasul
mid'Oraisa. We must be stringent about a Safek. If
the majority is Kosher and a minority is She'uvim,
it is Pasul mid'Rabanan, so we are lenient about a
i. Beis Yosef (DH veha'Ran): The Ra'avad holds
that She'uvim is Pasul mid'Oraisa if one poured
the water in. If by itself the water came from
the Kelim to the Mikveh, it is Pasul
mid'Rabanan. R. Shimshon holds that She'uvim in
a Keli that is Mekabel Tum'ah is Pasul
mid'Oraisa. If the Keli is not Mekabel Tum'ah,
e.g. it is of stone, the Mikveh is Pasul
IS THE PESUL OF MAYIM SHE'UVIM EVER MID'ORAISA? (Yevamos 82)
Index to Halachah Outlines for Maseches Bava Basra