ONE MUST GO BACK UP TO A MIL
(R. Yosi bar Chanina): Four Mil is the Shi'ur in the direction one was going, but one need not backtrack even one Mil.
Inference (Rav Acha bar Yakov): If he can obtain them by backtracking less than one Mil, he must do so.
TUM'AH AND YADOS FOR SKIN
(Beraisa): If a troop of soldiers on the way to war entered a house, the contents are Tamei, because a troop always carries skins of heads (for witchcraft).
This is not surprising. Kings put on their heads the skin of R. Yishmael's head.
(Mishnah): If one flays any animal to make a mat:
If he only flayed the amount needed to hold (grip) the skin, this can transmit Tum'ah (like a Yad; one opinion in Tosfos says, like a Shomer).
If he flays to make a water pouch, it is Tamei (like a Yad or Shomer) until the chest;
If he flays from the legs, the entire skin is Tamei.
R. Yochanan ben Nuri says, the skin on the neck is not connected regarding Tum'ah;
Chachamim say, all the skin is Tamei until he finishes flaying.
(Gemara) Question: What is the law after flaying enough to hold the skin?
Answer #1 (Rav): All the flayed skin is Tahor.
Answer #2 (Rav Asi): The last Tefach flayed (the Tefach adjacent to where the skin is still attached) is Tamei.
Question (Beraisa): If one flays more than enough to hold the skin, one who touches the flayed skin is Tahor.
Suggestion: This includes the last Tefach flayed.
Answer: No, it excludes the last Tefach flayed.
Question (Beraisa): The skin opposite (still on) the flesh is Tamei.
Inference: The last Tefach flayed is Tahor.
Answer: No. "Skin opposite the flesh" includes the last Tefach flayed.
Question (Beraisa): If one flays any animal to make a mat, the amount needed to hold the skin, this is Tamei;
The last Tefach flayed is Tahor.
Answer: The case is, only two Tefachim have been flayed. Rav Asi's law applies only when more has been flayed. (Then, the last Tefach is useful.)
(Beraisa #1): One Tefach is needed to hold the skin.
Contradiction (Beraisa #2): Two Tefachim are needed to hold the skin.
Resolution (Abaye): Beraisa #1 discusses a double Tefach (it equals two regular Tefachim).
Support (Beraisa): A double Tefach is needed to hold the skin.
BREAKING A KLI TO MAKE IT TAHOR
(Mishnah): If a man was ripping a Tamei cloak to be Metaher it, once he rips the majority, it becomes Tahor. (Tosfos - this is retroactive, from when he started tearing.)
(Rav Nachman): This is only if it is a Tevul Yom. (It was immersed today. Even if it were not torn, it would be fully Tahor tonight);
Since he was willing to immerse it (even though this is bad for it), we are not concerned lest he not tear the majority.
If he did not immerse it, we decree that he must tear it fully to be Metaher it, lest he not tear the majority.
Objection #1 (Rabah): We must decree that tearing the majority is not Metaher on the day it became Tamei, lest people will think that Kelim become fully Tahor through immersion on the same day!
Objection #2 (Rabah): R. Eliezer b'Rebbi Shimon forbids severing the Simanim of Olas ha'Of during Melikah. We cut only the majority;
He does not decree (Tosfos - that he must cut a large majority) lest he not cut the majority!
Answer (to Objection #1 - Rav Yosef): People will see that the majority was torn and understand that this was Metaher it, and not the immersion.
Answer (to Objection #2 - Rav Yosef): Kohanim (who do Melikah) are zealous. We need not decree lest they not cut enough.
Question (against Rav Nachman - Mishnah): If one flays any animal, Tamei or Tahor, to make a mat:
If he flayed only the amount needed to hold the skin, it is Tamei;
If he flayed more, it is Tahor. We do not decree lest he flay only the amount needed (and mistakenly think that it is Tahor)!
Answer: Regarding Tum'ah mid'Oraisa, we would make such a decree;
The Mishnah discusses only Tum'ah mid'Rabanan.
Question: Granted, we can say that the Tum'ah is mid'Rabanan regarding a Tahor animal, e.g. the man is Tamei mid'Rabanan;
However, the Mishnah discusses also a Tamei animal. It is (a Nevelah, which is) Tamei mid'Oraisa!
Answer: The Mishnah does not discuss Tamei species, rather, a Terefah of a Kosher species, which is Tamei mid'Rabanan.
Question: A Terefah is not Tamei!
Answer: It can be, like Shmuel's father taught;
(Shmuel's father): If a Terefah Kodesh animal was slaughtered, it is Tamei mid'Rabanan.
Question (against Rav Nachman - Beraisa - R. Dostai ben Yehudah): If one flays a Sheretz, the flayed skin is connected (and is Metamei like the Sheretz) until he flays it all.
Inference: (This is because it is hard to flay Sheratzim. However,) if one flays a camel, only Kedei Achizah (the amount needed to hold onto) is connected! (Even though the Tum'ah is mid'Oraisa, we do not decree to be Metamei past Kedei Achizah due to within Kedei Achizah!)
Answer: No. Rather, regarding a camel, the skin on the neck is not connected;
The Beraisa is like R. Yochanan ben Nuri (in our Mishnah).
Version #1 (Rav Huna): If one tears the majority of a cloak:
The resulting pieces are Tehorim only if neither is large enough to make a turban;
If a piece is big enough, it is Tamei.
(Reish Lakish): Tearing the majority is Metaher only for a cloak;
Skin is strong (it can be sewn together like before), so it remains Tamei.
(R. Yochanan): Also regarding skin, tearing the majority is Metaher, for it is not strong.
Question (R. Yochanan - Mishnah - R. Yehudah): If skin is Tamei Midras (it is made to be sat on, and a Nidah (or Zav... ) sat on it, making it an Av ha'Tumah):
If the owner planned to cut it into straps or shoes, once he starts cutting it, it is Tahor;
Chachamim are Metamei until he cuts it into pieces less than five (by five) Tefachim.
Summation of question: Less than five Tefachim is Tahor. We do not say that since it is strong, we consider it to be connected!
Answer: Reish Lakish considers it connected only when it is cut down the middle, but not when strips are cut from the edges.
Question (R. Yirmeyah - Mishnah): If one flays any animal, Tamei or Tahor, to make a mat:
If he flayed only the amount needed to hold the skin, it is Tamei.
If he flayed more, it is Tahor. We do not consider it to be connected because the skin is strong!
Answer (R. Avin): Each piece flayed is considered disconnected, for it will not be joined to the meat again.
Question (against Reish Lakish - Rav Yosef - Mishnah): R. Yochanan ben Nuri says, the skin on the neck is not connected regarding Tum'ah.
According to Reish Lakish, we should consider it to still be connected!
Counter-question (Abaye - Seifa - Chachamim): It is connected.
This supports Reish Lakish and opposes R. Yochanan!
Answer (to both questions - Abaye): The Tana'im argue about a Shomer that will become detached by itself;
Chachamim consider to be it a Shomer. R. Yochanan ben Nuri does not.