THE TRADITION USED FOR THE KAL VA'CHOMER [line 1]
Question: Which law was a tradition, and which was (not a tradition, and was used) for the Kal v'Chomer?
Possibility #1: The tradition was that a Nazir shaves for a bone k'Se'orah. Tum'as Ohel of a Revi'is of blood was not a tradition.
Possibility #2: The tradition was Tum'as Ohel of a Revi'is of blood. It was not a tradition that a Nazir shaves for a bone k'Se'orah.
Answer (Beraisa): A Nazir shaves for a bone k'Se'orah. This is a tradition from Sinai, so it cannot be used in a Kal v'Chomer to teach that he shaves also for a Revi'is of blood.
WHEN IN DOUBT WHICH NAZIR IS TAMEI [line 7]
(Mishnah): If a man told two Nezirim 'I saw that one of you became Tamei, but I do not know which', they shave and bring (collectively) the Korbanos of a Tahor Nazir and a Tamei Nazir;
One of them says 'if I was Tamei, Korbanos Nazir Tamei were mine, and Korbanos Nazir Tahor were yours. If I was Tahor, vice-versa.'
They observe 30 more days of Nezirus, and bring Korbanos Nazir Tahor. They stipulate that these Korbanos are for the one who was Tamei.
(Gemara) Question: Since a third person saw them, why do we consider them to be Safek Teme'im?
We learn about Safek Tum'ah in a Reshus ha'Yachid (a private domain) from Sotah.
There, only two were present (she and the suspected adulterer). The law of Safek Tum'ah in a Reshus ha'Yachid (it is considered definite Tum'ah) applies only when at most two were present!
When there are three, we apply the law of Safek Tum'ah in a Reshus ha'Rabim (it is considered definitely Tahor)!
Answer (Rabah bar Rav Huna): The observer saw, from afar, Tum'ah thrown between the two Nezirim (there were not three people together).
Support (Rav Ashi - Mishnah): I do not know which of you became Tamei.
This connotes that he never knew.
SHAVING WHEN IN DOUBT [line 2]
(Mishnah): They shave and bring Korbanos...
Version #1 - Question: Why may they shave (the second time)? The second shaving of the one who was Tahor is not for Nezirus, so he transgresses cutting the Pe'os (sideburns)!
Answer (Shmuel): The case is, the Nezirim are women or children (who may cut their Pe'os).
Question: Why didn't Shmuel say that they can be men, and one does not transgress for Hakafas Kol ha'Rosh (cutting all the hair on the head, including the Pe'os)?
Inference: Shmuel forbids Hakafas Kol ha'Rosh.
Version #2 (Mar Zutra - Mishnah): If a Nazir became Safek Tamei (Mes), and he was a Safek Metzora Muchlat, he can eat Kodshim after 60 days. He shaves four times (twice for (Safek) Tzara'as, for (Safek) Nazir Tamei, and for Nazir Tahor).
Question: Why may he shave four times? He transgresses Hakafah (if he was not a Muchlat or not Tamei Mes, some of these are unnecessary! The text of Rashi and Tosfos says 'he transgresses shaving (the beard), i.e. if he was not a Muchlat.)
Answer (Shmuel): The case is, the Nazir is a woman or child (they are permitted to shave the beard and sideburns).
WHO IS COMMANDED ABOUT THE PE'OS? [line 11]
(Rav Huna): One who cuts the Pe'os of a child is liable.
Rav Ada bar Ahavah: Who cuts your children's Pe'os?
Rav Huna: Chovah (my wife) cuts them.
Rav Ada: She should bury her sons! (If you obligate a man who cuts a boy's Pe'os, also a woman is liable! Rav Huna disagreed (see below). Rosh - this was not a curse. Rather, he asked, is she not concerned lest she be punished, and will bury her sons?!)
For the duration of Rav Ada's life, Rav Huna did not have children (from her) that survived.
Rav Huna and Rav Ada both forbid Hakafas Kol ha'Rosh.
Question: What do they argue about?
Answer: Rav Huna equates "do not round the corners of your head" and "do not destroy the corners of your beard." Whoever is commanded about the beard is commanded about the Pe'os;
Since women are not commanded about the beard, they are not commanded about the Pe'os.
Rav Ada holds that the verse equates the Makif (one who cuts Pe'os) and the Nikaf (one whose Pe'os are cut);
Whenever the Nikaf is liable, the Makif is liable.
The Torah does not punish children. Since a child is exempt, one who is Makif a child is exempt.