(Mishnah): There are three Isurim of a Nazir: Tum'ah, shaving, and consuming what comes from the vine.

There is a stringency of Tum'ah and shaving that does not apply to eating of the vine. If a Nazir became Tamei or shaved, he (usually) must observe additional days of Nezirus, but not if he ate from the vine;

There is a stringency of eating of the vine that does not apply to Tum'ah and shaving. Eating from the vine is never permitted to a Nazir, but shaving and Tum'ah are permitted, for the Mitzvah (for a Metzora) to shave and for a Mes Mitzvah.

There is a stringency of Tum'ah that does not apply to shaving. Tum'ah totally nullifies all days observed until then, and obligates him to bring Korbanos, but shaving does not nullify more than 30 days, and does not obligate Korbanos.

(Gemara): Tum'ah [is forbidden], for it says "Kol Yemei Haziro la'Shem Al Nefesh Mes Lo Yavo";

Shaving [is forbidden], for it says "Kol Yemei Neder Nizro Ta'ar Lo Yavo Al Rosho";

What comes from vines [is forbidden], for it says "Kol Yemei Nizro mi'Chol Asher Ya'aseh mi'Gefen ha'Yayin..."

(Mishnah): There is a stringency of Tum'ah and shaving over what comes from the vine.

Tum'ah [cancels], for it says "Kol Yemei Haziro la'Shem [Al Nefesh Mes Lo Yavo]";

Shaving [cancels], for it says "veha'Yamim ha'Rishonim Yiplu Ki Tamei Nizro" (we expound that Tum'ah cancels because it obligates him to shave, and shaving cancels. We explained this like PNEI MOSHE.)

(Mishnah): There is a stringency of eating (it is not permitted, even for a Mitzvah) that does not apply to Tum'ah and shaving.

Assumption: They wanted to say that this refers to four cups of wine [of Pesach, since they are only mid'Rabanan], but if he swore to drink wine, and became a Nazir, he drinks!

Rejection: [Our Mishnah] comes to teach that he does not drink.

Shaving for a Mitzvah is permitted. This is not only to become Tahor from his Tzara'as. Rather, it is even to make a Siman for his Nesek (a plague where there is hair; he shaves around it), to know whether [the Nega] spread or did not spread.

[Tum'ah is permitted] for a Mes Mitzvah. This is like a Mishnah teaches, if a Kohen Gadol and Nazir were walking on the road and found a Mes Mitzvah...

There is a stringency of Tum'ah over shaving. [Tum'ah cancels all the days and obligates him to bring Korbanos], for it says "veha'Yamim ha'Rishonim Yiplu... v'Hevi Keves Ben Shenaso l'Asham.

There is a stringency of shaving. One who shaves [a Nazir] is [liable,] like the one who shaved, but one who is Metamei him is not like one who becomes Tamei.