Zevachim Daf 19 זבחים דַף 19

The Gemara presents eight questions about חציצה for בגדי כהונה. (1) נכנסה לו רוח בבגדו – What if a wind entered [the כהן’s] clothing, creating space between the בגד and his body? "על בשרו" בעינן – Do we require the בגד to be physically “on his flesh,” which it is not, or do we say דרך לבישה בכך – this is a normal manner of wearing clothing? (2) Do lice constitute a חציצה? Dead lice certainly are, but if it is alive, do we say that since it comes and goes on the body, רביתא היא – it is considered like a natural growth of the body, or since it bothers him, it is a חציצה? (3) Is dust of earth (which is unnoticeable) a חציצה? (4) Is space under his armpit considered a חציצה, since it is not physically touching his body, or not, since it is the normal manner of wearing? (5) If he puts his hand into his clothing, גופו מי חייץ – does his own body constitute a חציצה? (6) Is a detached thread still stuck in the garment a חציצה? (7) If his hair ran under his garment, is it a חציצה, or is it like his body (assuming his body is not a חציצה)? (8) Are tefillin a חציצה?

A Baraisa describes the procedure of קידוש ידים ורגלים. The Tanna Kamma says: מניח ידו הימנית על גבי רגלו הימנית – he places his right hand upon his right foot, and his left hand upon his left foot, ומקדש – and he sanctifies them by releasing water from the כיור onto both hands and feet simultaneously. Rebbe Yose bar Rebbe Yehudah says he places his hands on top of each other, which he places on top of his feet which are placed on top of each other, and is מקדש. The Rabbonon told him: הפלגתה אי אפשר לעשות כן – You have exaggerated; it is impossible to do so without falling! Rav Yosef explains: וחבירו מסייעו – he washes whiles his colleague supports him so he does not fall. Abaye explains the Tannaim argue if עמידה מן הצד – standing with support from the side is considered standing. The Rabbonon do not consider this halachically standing, so he must stand without support. He cannot be מקדש while sitting, because the passuk says "לשרת" – to serve, ושירות מעומד הוא – and service must be performed while standing.

In a Baraisa, Rebbe says that if a Kohen was מקדש his hands and feet during the day, he does not need to do so again that night, but if he was מקדש by night, he needs to be מקדש again the next day, because Rebbe holds לינה מועלת בקידוש ידים ורגלים – the passage of night is effective in disqualifying the sanctification of hands and feet, thus requiring a new קידוש. In another Baraisa, Rebbe adds that even if he performed avodah the entire night, he must be מקדש again the next morning, even though there was no interruption between the עבודות. Rebbe Elazar bar Rebbe Shimon says in both Baraisos that a Kohen does not need a new קידוש the next day, because he holds אין לינה מועלת בקידוש ידים ורגלים, and a single קידוש can even be valid for ten days. Rebbe’s opinion is derived from the word "בגשתם" – when they approach (to do avodah), thus requiring a new קידוש for each new “approach;” each day’s avodah constitutes a new “approach,” since the wood on the מזבח is arranged daily. Rebbe Elazar bar Rebbe Shimon darshens the word "בבואם" – when they come (to the Mikdash), indicating that קידוש is only required each time he enters.