GEMARA: A dilemma was raised before the Sages with regard to the halakha transmitted to Moses from Sinai mentioned in the mishna: Is the halakha that a nazirite must shave for a bone that is a barley-grain-bulk a halakha transmitted to Moses from Sinai, and it was the status of a quarter-log of blood that Rabbi Akiva sought to derive as an a fortiori inference, and with regard to this claim they said: One does not derive an a fortiori inference from a halakha transmitted to Moses from Sinai?

Or perhaps the ruling that a quarter-log of blood imparts ritual impurity in a tent is the halakha transmitted to Moses from Sinai, and Rabbi Akiva sought to use the case of a bone that is a barley-grain-bulk as the source of an a fortiori inference that a nazirite must shave for a quarter-log as well, to which the Sages replied that one does not derive an a fortiori inference from a halakha transmitted to Moses from Sinai. The Gemara answers: Come and hear the unequivocal statement of a baraita: A bone that is a barley-grain-bulk is a halakha, and a quarter-log of blood is an a fortiori inference, and one does not derive an a fortiori inference from a halakha.

MISHNA: With regard to two nazirites, where one other person said to them: I saw one of you become impure, but I do not know which one of you it was, they must each complete their naziriteship terms, shave their hair, and both together bring an offering of ritual impurity and an offering of purity, due to the uncertainty. And one of them says to the other: If I am the impure one, the offering of impurity is mine and the offering of purity is yours; and if I am the pure one, the offering of purity is mine and the offering of impurity is yours.

And because of the uncertainty they each count a further thirty days of naziriteship and both together bring an offering of purity. And one of them says: If I am the previously impure one, that offering of impurity sacrificed earlier was mine, and the offering of purity was yours; and this offering sacrificed now is my offering of purity. And if I am the previously pure one, the offering of purity brought earlier was mine, and the offering of impurity was yours; and this current offering is your offering of purity.

GEMARA: The mishna teaches with regard to two nazirites, that if one other person said to them: I saw one of you become impure, but I do not know which one of you it was, they must bring an offering of ritual impurity and an offering of purity. The Gemara expresses surprise at this case: But why should they be defined as having uncertain impurity? After all, the general principle that any uncertain impurity in a private domain is considered impure, from where do we derive this? From the case of a sota.

Yet this situation is not similar to that of a sota, as just as the case of a sota involves only an adulterer and an adulteress, so too any uncertain impurity in a private domain is considered impure only in a case where there are no more than two people present. However, in the mishna here there are two nazirites and this other individual who is standing alongside them, who witnessed one of them become impure, which makes a total of three. Consequently, this is an uncertain impurity in the public domain, as three people are sufficient for the place to be considered a public domain with regard to this halakha, and the halakha with regard to any uncertain impurity in the public domain is that its uncertainty is considered pure.

Rabba bar Rav Huna said that the mishna is referring to one who says: From a distance I saw an impure item thrown between you. Since he was not with them when one of the nazirites became impure, there were only two people present and therefore this is a case of uncertain impurity in a private domain. Rav Ashi said: The language of the mishna is also precise,