1) TOUCHING PARTS OF THE BODY IN THE MORNING WITH UNWASHED HANDS
QUESTION: The Gemara says that a person should not touch his eyes, nose, mouth, ear, scab, Amah, rectal area (Pi ha'Taba'as), or a beer-barrel before he washes his hands in the morning upon rising. The TUR (OC 4) cites only the first four. Why does he leave out the other four?
ANSWERS:
(a) With regard to touching the Amah and Pi ha'Taba'as, the BEIS YOSEF explains that the Tur may understand the Gemara like RASHI (DH Ma'aleh), who explains that touching the Amah and Pi ha'Taba'as is unrelated to one's unwashed hands in the morning. Rather, touching those areas is always forbidden. Touching the Amah leads to Keri, and touching the Pi ha'Taba'as causes rashes. Therefore, the Tur has no need to mention those parts in this Halachah. Similarly, the Tur does not mention touching a scab, because a scab also should not be touched at any time for health reasons.
With regard to why the Tur omits mention of a barrel, the Beis Yosef writes that touching a barrel, too, is unrelated to one's unwashed hands in the morning. Rather, touching a beer barrel anytime causes the beer to spoil. Therefore, it is not relevant to the Halachah of touching things in the morning with unwashed hands.
(b) The BACH, TAZ, and VILNA GA'ON disagree. They ask that according to the Beis Yosef's explanation, why does the Gemara say that "the hand that touches a barrel should be caught off"? Just because a person ruins his beer is no reason to say that his hand should be cut off! (It could be that the Beis Yosef understands that Gemara refers to touching and ruining someone else's beer.) They therefore explain that a barrel should be included in the Tur's list of things that a person should not touch with unwashed hands in the morning.

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