הנוגע בכחצי זית ודבר אחר מאהיל עליו ועל כחצי זית טהור
in the case of one who touches half an olive-bulk of flesh from a corpse and simultaneously another item overlies both him and half an olive-bulk of flesh from a corpse, he remains pure.
ואי חד שמא הוא אמאי טהור אלא קשיא רישא
But if impurity via contact and via a tent are considered one concept, why does he remain pure? Rather, based on the latter clause of the mishna, the first clause of the mishna is difficult, because it indicates that these two categories of impurity are considered one concept and join together to constitute the requisite measure for impurity.
אמר רבי זירא בטומאה רצוצה בין ב' מגדלים עסקינן ואין ביניהן פותח טפח דכולה נגיעה היא
Rabbi Zeira said: In the first clause of the mishna we are dealing with a case where the source of impurity is pressed between two wooden chests and there is no opening of one handbreadth in between the chests. When the hand of a person overlies the chests, the impurity of the pressed item rises beyond the chests and it transmits impurity to the person. Therefore, his interaction with all the sources of impurity is considered as though he is touching them simultaneously. Consequently, there is no proof in the mishna for the opinion of Rabbi Yoḥanan that imparting impurity via contact and via a tent are considered the same concept.
ומאן תנא דקרי לאהל נוגע ר' יוסי היא דתניא ר' יוסי אומר מלא תרווד רקב מטמא במגע ובמשא ובאהל
Therefore, the Gemara asks: Who is the tanna who refers to impurity imparted in a tent as one who touches [noge’a]? The Gemara answers: It is Rabbi Yosei, as it is taught in a baraita (Tosefta, Oholot 4:1): Rabbi Yosei says: A full ladle [tarvad] of dust from a corpse imparts impurity like the corpse itself in three ways: By contact [bemagga], and by carrying, and in a tent.
בשלמא במשא ובאהל הא קא טעין ליה לכוליה והא קא מאהיל אכוליה אלא נוגע הא לא נגע בכוליה אלא לאו ש"מ מאי נוגע מאהיל
Granted, the dust of a corpse imparts impurity via carrying and in a tent; this one who carries it carries the entire amount of dust and that one who overlies the dust overlies all of it. But with regard to one who touches it, one does not touch all of the dust, and it should therefore be impossible for one to become impure via contact. Rather, isn’t it correct to conclude from this baraita: To what is the term noge’a referring? It is referring to one who overlies the dust.
והא קתני נוגע והא קתני מאהיל אמר אביי למטה מטפח אהל נגיעה למעלה מטפח אהל גרידא
The Gemara asks: How is it possible to explain the baraita in such a manner? But doesn’t Rabbi Yosei teach the case of one who touches separately, and doesn’t he teach the case of one who overlies separately? Therefore, the term noge’a cannot be referring to overlying. Abaye said: That is not difficult because there are two types of overlying. With regard to a tent that overlies impurity at a height of below one handbreadth, that tent is referred to as touching. But a tent that overlies impurity at a height of above one handbreadth is referred to as merely a tent.
רבא אמר אפילו למעלה מטפח נמי אהל נגיעה הוא והיכי דמי אהל גרידא בהמשכה
Rava said: According to Rabbi Yosei, even a tent that overlies impurity at a height above one handbreadth is referred to as touching. And what are the circumstances of a tent that is referred to as merely a tent and not as touching? The term tent is referring to the case of a structure that overlies both a person and a source of impurity, thereby spreading the impurity from its source to the person.
אמר רבא מנא אמינא לה דתנן ר' יוסי אומר חבילי מטה וסריגי חלונות חוצצין בין הבית לעלייה שלא להכניס טומאה לצד שני
Rava said: From where do I say my opinion? It is as we learned in a baraita (Tosefta, Oholot 9:4) that Rabbi Yosei says: With regard to bundles that serve as a bed and grilles taken from windows, if one placed them between the ground floor and the upper floor of the house such that they serve as a ceiling, since they have become part of the building they are not susceptible to impurity. Therefore, even if there are holes in the bundles and the grilles, they serve as a barrier between the house and the upper floor such that the impurity of a corpse present in the area of the house cannot enter the other side, i.e., the upper floor.
פרסן על פני המת באויר הנוגע כנגד הנקב טמא שלא כנגד הנקב טהור
And if one spread out the bundles and grilles outside the house in an impermanent manner by hanging them over a corpse in the air like a net, one who touches, i.e., overlies the corpse, opposite a hole in the netting becomes impure. By contrast, one who overlies it not opposite a hole remains pure.
ה"ד אילימא למטה מטפח שלא כנגד הנקב אמאי טהור מת בכסותו הוא ומת בכסותו מטמא
Rava explains his proof: What are the circumstances? If we say that he spread out the netting below the height of one handbreadth above the corpse, why does one who overlies the corpse not opposite a hole in the netting remain pure? In such a case, the netting is close enough to the corpse to be considered part of the clothing of the corpse. Therefore, the case is tantamount to one where the corpse is dressed in its clothing, and a corpse dressed in its clothing imparts impurity to one who overlies it because the clothing does not act as a barrier.
אלא לאו למעלה מטפח וקא קרי ליה נוגע
Rather, is it not the case that he spread out the netting more than one handbreadth above the corpse? And Rabbi Yosei refers to overlying the corpse as touching. Apparently, contrary to the opinion of Abaye, Rabbi Yosei refers to overlying as touching even when the overlying item is more than one handbreadth above the source of impurity.
אמר אביי לעולם למטה מטפח ודקאמרת מת בכסותו הוא מת בכסותו מבטל ליה האי לא מבטל ליה
Abaye rejected Rava’s proof and said: Actually, the case is one where one spread the netting out below the height of one handbreadth above the corpse. And with regard to that which you say: If so, one who overlies the corpse not opposite a hole in the netting should also become impure as it is tantamount to a case of a corpse dressed in its clothing, this case is not similar to the case of a corpse dressed in its clothing. In the case of a corpse dressed in its clothing the clothing does not act as a barrier to the impurity because the one who dressed the corpse nullified the clothing by rendering its status as though it is a part of the corpse. But in this case in the baraita, the one who spread out the netting over the corpse intended to remove the bundles and grilles afterward and he did not nullify them.
ותהוי כטומאה טמונה בוקעת ועולה קסבר רבי יוסי טומאה טמונה אינה בוקעת
The Gemara objects with regard to Abaye’s explanation: But if the case is one where he spread out the netting less than one handbreadth above the corpse, even if it is not considered the clothing of the corpse, let it be considered like a source of impurity hidden underneath an overlying structure at a distance of less than one handbreadth. In such a case, the impurity breaks through and ascends, and therefore it should transmit impurity even to one who overlies it not opposite a hole in the netting. The Gemara explains: Rabbi Yosei holds that hidden impurity does not break through and ascend.
ומנא תימרא דתנן תיבת המגדל שיש בה פותח טפח ואין ביציאתה פותח טפח טומאה בתוכה הבית טמא טומאה בבית מה שבתוכה טהור
And from where do you say that this is the opinion of Rabbi Yosei? It is as we learned in a mishna (Oholot 4:2): In the case of a compartment in a chest that is inside a house, in which the open space of the compartment itself has at least one cubic handbreadth in volume, but the opening of the compartment to the house does not have the area of one square handbreadth, and the volume of the entire chest is forty se’a, in that case, if there is a source of impurity inside the compartment, the compartment does not act as a barrier and the house is impure. If the source of impurity is inside the house but outside the chest, whatever is inside the compartment remains pure, because the opening of the compartment is less than one handbreadth.
מפני שדרך טומאה לצאת ואין דרך טומאה ליכנס
This differentiation exists because it is typical for a source of impurity to exit from its location, and therefore impurity can be transmitted out of the compartment and into the house. But it is not typical for a source of impurity to enter a location, and therefore an impure item that lies in the house does not transmit impurity into the compartment. Since the volume of the chest is forty se’a it constitutes a separate tent, and the compartment that is part of the chest is also considered part of this tent.
ורבי יוסי מטהר מפני שיכול הוא להוציאה לחצאין או לשורפה במקומה
And Rabbi Yosei deems the house pure when the impure item is in the compartment. The item will not necessarily impart impurity outside of the compartment because one can remove the source of impurity from the compartment in halves, i.e., in pieces that each measure less than the requisite amount to impart impurity. Or, alternatively, one can burn the source of impurity while it still remains in its place inside the compartment.
וקתני סיפא העמידה בפתח ופתחה לחוץ טומאה בתוכה הבית טהור טומאה בבית מה שבתוכה טהור
And the latter clause of that mishna teaches: If one placed the chest in the entrance to the house and the opening of the compartment is facing out of the house, if there is a source of impurity inside the chest, the house remains pure because the impure item will typically exit the house. If there is a source of impurity in the house, whatever is inside the chest remains pure, because the source of impurity will not enter the chest.