Rabah asks how would the money be used if there are more than one son who is
a Nazir? Is the money split equally among the sons like any Yerushah, or
does the first son (either the first who uses it, or the first who became a
Nazir) get to keep it?
Rava then asks how the money would be used when there is a son who is a
Bechor and another, normal son (a "Pashut"). Do we say that it is a Halachah
l'Moshe mi'Sinai and therefore they do not split it according to the amount
of Yerushah that they normally receive, or do we say that it is a Yerushah,
and just like the Bechor receives a double portion ("Pi Shenayim") of the
rest of the estate, he receives a double portion of this money, too.
Rava continues and asks that if it is a Yerushah and the Bechor receives the
money according to his share ("Pi Shenayim") of the father's estate, "is it
only with Chulin that the Bechor takes a double portion, or even with
Hekdesh?"
What is Rava's second question? The money that the father set aside was
obviously Hekdesh, since the Halachah l'Moshe mi'Sinai only applies to Ma'os
Setumin (unspecified money designated for Korbanos) which the father set
aside for his Korbanos Nezirus, like the Mishnah says! If the money is
Chulin, then it is obvious that the brothers split it the same way that they
split all of the other Chulin assets of the father's estate!
(a) The ROSH seems to understand that Rava is not asking a second question.
Rather, the Gemara is simply adding explanation to Rava's question. Rava
wants to emphasize that even if it is clear that the money is treated like a
Yerushah, there is still reason to say that the Bechor should not receive
"Pi Shenayim" of this Yerushah. There are some types of assets in a Yerushah
of which the Bechor does not receive "Pi Shenayim" (such as Ra'uy, etc.),
and perhaps Hekdesh is treated like those Yerushos that the Bechor and other
sons split equally. (Perhaps a reason why the money should be comparable to
Ra'uy is because the sons cannot use it until the end of their Nezirus
period.)
(b) RABEINU TAM (cited by Tosfos DH Ba'i) explains that Rava's second
question applies even if the Bechor does receive "Pi Shenayim" from the
money. Perhaps that only applies only when the father designated the money
by saying, "this money is for my Nezirus." But if the father designated the
money by saying, "This money is for the Korbanos of my Nezirus," then
perhaps the Bechor receives only a portion equal to that of the rest of the
sons.
It is unclear why there should be a distinction between the two statements,
and in either case the money should be Hekdesh since the father designated
the money for his Nezirus. It should not make a difference whether he
mentioned "the Korbanos" of his Nezirus or not.
The Rosh (who calls this explanation "strange") seems to understand that the
question is asking to what kind of Ma'os Setumin does the Halachah l'Moshe
mi'Sinai apply? Does it apply only to money that was set aside for Nezirus,
in which case he could use the money for any or all of the Korbanos? Or does
it apply even to money that was set aside for "Korbanos Nezirus" and must be
used for all three Korbanos and not for any individual Korban (see Tosfos,
beginning of 25a)?
The Rosh points out that according to this, Rava's second question has
nothing to do with a Bechor. Why, then, does Rava ask the question in a case
where the father has two sons and one is a Bechor? He could ask the same
question in a case where the father has one son!
Perhaps Rabeinu Tam had a different intention. Rava's question is whether
the Bechor receives "Pi Shenayim" of money of Hekdesh when the Hekdesh is
"Mevurar," clearly specified, such as when the father said that the money
will be used for three specific Korbanos. When the money is not specified
but instead could be used for any one of or for all three Korbanos, then it
is more obvious to Rava that the money should be treated like Chulin and the
Bechor should receive "Pi Shenayim" like he receives from the rest of the
estate. The logic for this might be that when the option is still there to
make the money into whichever Korban he wants, then the sons could put the
money to use immediately by declaring for which Korban it will be used. If,
on the other hand, the money is already designated for specific Korbanos,
then the sons cannot use it until they actually bring those specific
Korbanos.
(c) The MEFARESH explains that the second question of Rava relates to the
status of the meat of the Korban after the sons offer it as a Korban Nazir.
Even if the Bechor receives two thirds of the money for his Nezirus, perhaps
his benefits as a Bechor extend only to spending the money on the purchase
of animals for his Nezirus. However, once the animal is sacrificed and its
meat is ready to be eaten, the brothers must split the meat equally, since a
Bechor does not receive "Pi Shenayim" from assets that are Hekdesh.
Why, though, should the Bechor not get to eat all of the meat if it is his
Korban? Perhaps the Mefaresh holds like RASHI in Bava Kama (12b, DH Aval
l'Achar; see Tosfos there) who says that even when the owner eats from a
Korban, his portion is coming from "Shulchan Gavohah" -- it is granted to
him from Hashem. The "Shulchan Gavohah" grants a portion to the owner of the
Korban. In our case, even though the son is the one who offers the Korban,
the father is still considered the owner. Since the father is not alive,
though, the beneficiary rights from "Shulchan Gavohah" go to his sons, who
are "b'Kar'a d'Avuha," an extension of their father. The question of the
Gemara is whether these rights that come because they are an extension of
the father grant the Bechor a double share of "Pi Shenayim," or whether he
splits it equally with the other brother because it is not a Yerushah.
(See also the OR SAME'ACH, Hilchos Nachalos 2:1, and CHIDUSHEI RABEINU MEIR
SIMCHAH here for other approaches.)