MISHNA: With regard to a nazirite who shaved for the conclusion of his naziriteship, and it later became known to him that during his naziriteship he was ritually impure from a corpse, if it was a known impurity, i.e., people were aware of the impurity when he became impure, he negates his entire naziriteship. And if it was ritual impurity imparted by a grave in the depths, one that was unknown at the time, he does not negate his naziriteship. If he discovered he was impure before he shaved, he negates his naziriteship in either case.

The mishna asks: How does one differentiate between a known and an unknown impurity? If a nazirite descended to immerse in a cave, and a corpse was found floating at the mouth of the cave, he is impure, as an openly visible corpse is a known impurity. What, then, is an impurity of the depths? This is referring to a case where the corpse was found sunk into the ground of the cave in such a manner that it was unknown.

However, even here the circumstances of the case must be taken into account. If one descended not to immerse himself in the water, as he was ritually pure, but to cool himself, he remains pure. If he was impure and entered the water to purify himself from the impurity from a corpse, he is impure. The reason is that something that has the presumptive status of impurity remains impure, and something that has the presumptive status of purity is pure, as there is a basis for the matter. It is reasonable that items or people retain their presumptive status.

GEMARA: The Gemara asks: From where are these matters derived, that there is a difference between known and unknown impurity? Rabbi Eliezer said that the verse states with regard to a nazirite: “And if any man shall die very suddenly beside him” (Numbers 6:9). The emphasis provided by the term “beside him” indicates that it is clear to him that he has become impure. However, one is not impure if the presence of the corpse is unknown.

Reish Lakish said a different source: The verse states with regard to the Paschal offering: “Any man of you who shall be ritually impure due to a corpse or on a road far away” (Numbers 9:10). The word “road” is juxtaposed in the verse to the term “ritually impure,” indicating that the impurity is like a road. Just as a road is in the open, so too, every impurity is in the open. It must be a known impurity.

The Gemara objects: But consider that which we learned in the Tosefta (Zavim 2:9): Which is the ritual impurity imparted by a grave in the depths? It is impurity imparted by any corpse of which no one is aware, even at the end of the earth. This type of impurity is permitted for both a nazirite and one who sacrifices the Paschal offering. However, if even one person is aware of it, even at the end of the earth, this is not impurity imparted by a grave in the depths.

The Gemara states its question: Granted, according to the one who says that this halakha is derived from the verse that states that ritual impurity is like a road, it is fine, as an item known to someone in the world can be compared to a road. However, according to the one who says that this halakha is derived from the term “beside him,” i.e., it is referring to an impurity that is clear to him, if one person at the other end of the earth is aware of this impurity, what of it? It was unknown to the nazirite himself.

And furthermore, consider that which is taught in another baraita (Tosefta, Zavim 2:8): In the case of one who finds a corpse lying across the width of a road, i.e., it had been buried there in such a way that it was impossible for the passerby to avoid becoming impure by passing over the corpse, then with regard to teruma, the passerby is impure. Therefore, if he is a priest, he may not eat teruma. However, with regard to both being a nazirite and being one performing the ritual of the Paschal offering, the passerby is pure. What is different about these situations? Rather, it must be that the halakha of impurity imparted by a grave in the depths is learned as a tradition and not from the verses, which are cited merely in support.

§ The mishna taught that if a nazirite discovered he was ritually impure before he shaved, he negates his naziriteship even if he was rendered impure by impurity of the depths. The Gemara asks: Who is the tanna who taught this opinion? Rabbi Yoḥanan says: It is Rabbi Eliezer, who says that shaving is indispensable to the completion of one’s naziriteship. Consequently, if he discovered he was impure before he shaved, he became impure during his naziriteship, and he negates the period he has observed.

Rami bar Ḥama raised a dilemma: What is the halakha with regard to one who became impure during the full term of the regular days of his naziriteship but his impurity became known to him only after the full term but before he shaved? Perhaps we go according to his knowledge, and it is a case of knowledge after the full term, or perhaps the halakha is not determined by the time of his awareness but by the actual time of the impurity, which occurred during his naziriteship. The Gemara adds: And with regard to what issue was this dilemma raised? It was with regard to his possible negation of the period he observed as a nazirite: Does he negate his naziriteship, or is he considered to have contracted impurity after the completion of his term, in which case he need not start his naziriteship afresh?