Explanation #1: Rashi explains that "Naga bi'Chenafo" refers to a Sheretz, "el ha'Lechem ve'ha'Lechem el ha'Nazid ... "?

Question #1: Rabeinu asks why "ve'el Kol Ma'achal" should mean "or any food, any more than all the others?

Question #2: Furthermore, why does Shmuel push to explain 'that what touched the corner of his garment'? Why does he not rather learn that "el Kol Ma'achal" is specific?

Question #3: Moreover, why does the Pasuk refer to a Sheretz as "Kanaf"?

Question #4: And furthermore, Ravina explains there that it is Revi'i ba'Kodesh, and here that it is a Shelishi, since the bread became an Av ha'Tum'ah when it touched a corpse ...

Question #4 (cont.): For do we not rule in ha'Mapeles (Nidah 28:) that 'Whatever is not subject to Tevilah in a Mikvah cannot become an Av ha'Tum'ah (and that includes food)?

Answer: This question one can answer however by restricting the principle of 'It cannot become an Av Ha'Tum'ah to its inability to be Metamei Adam ve'Keilim, but regarding being Metamei food and drink, it can.

Explanation #2: Rabeinu Tam therefore explains that the Sheretz touched the corner of the garment, which became a Rishon the corner then touched the bread or the cooked dish, one of which touched the wine or the oil, that makes three, and "ve'el Kol Ma'achal" makes four.

Explanation #2 (cont.): And the Pasuk presents them in this order to avoid any of the items being Metamei something like itself (e.g. food being Metamei food).

Explanation #2 (cont.): And Shmuel extrapolated from the word "bi'Chenafo" that there is a Chamishi.

Conclusion: Now it is clear why Ravina here mentions a Shelishi - since when the corner touched the Meis it became an Av ha'Tum'ah, like all Keilim do.

Question: On the contrary, there is more reason to render blood Tahor, even by Keilim, since the blood of Kodshim is not compared to water ...

Source: As we learned earlier - since it is not spilled like water, it is not Machshir.

Answer: The Gemara is referring to blood which is Metamei, such as the blood of Chulin, of Kodshim animals that are blemished of a Korban that became Pasul.

Halachah: From here, says the Ri, we can extrapolate that a Mikvah that comprises drawn water exclusively is only Pasul mi'de'Rabbanan.

Proof #1: This is because the Mashkin bei Mitbachaya which is Tahor, can only be speaking about Mayim She'uvin, seeing as the Gemara draws a distinction between blood and water, and not between drawn water and water that is attached,

Proof #1 (cont.): And it then goes on to say it is fit to Tovel needles and forks.

Proof #2: And we also learned in a Tosefta in Maseches Mikva'os (perek 2) that 'A Mikvah that one left empty and subsequently found full is Kasher' - because of the principle 'S'feika de'Rabbanan, le'Kula'.

Proof #2 (cont.): And 'empty' a lso implies that there was nothing in it, since it did not say that he left it lacking.

Implied Question: And although the Beraisa in Toras Kohanim commenting on the Pasuk "Ach Ma'ayan u'Bor", states 'I would have thought that a Mikvah is Kasher even if one filled it by carrying the water on one's shoulders. Therefore the Torah writes "Ma'ayan" (a fountain) - and just as a fountain is formed by a Divine source, so too must a Mikvah'.

Answer: One is forced to say that that (D'rashah) is an Asmachta.

Question: Seeing as a Mikvah that is completely Sha'uv is Kasher min ha'Torah, why did the Rabbanan see fit to decree on Mayim She'uvin at all?

Answer: The decree of Mayim she'uvin is based on the fear that one may otherwise come to Tovel inside a vessel, which is definitely Asur mi'd'Oraysa.

Clarification: The Ri says that even though they negated the Din of a Revi'is of a Mikvah, they did not negate the Kol Sh'hu of a Ma'ayan.

Proof: And we know this from the Toras Kohanim which states that 'A Ma'ayan renders Tahor even with only a Kol sh'hu, a Mikvah requires forty Sa'ah'.

Proof (cont.): Now the fact that a Mikvah requires forty Sa'ah speaks after they negated the Din of a Revi'is, yet it concludes that a Ma'ayan renders Tahor with a Kol Sh'hu.

Question: The Ri in the name of R. Sh'lomoh asks from the Gemara in Perek Chomer ba'Kodesh (Chagigah, 22.) in connection with a Mikvah which they divided with a basket - 'I will prove that one needs a hole that is equivalent to the tube (mouthpiece) of a flask, since the ground is full of tiny holes, and we need forty Sa'ah in one location.'

Question (cont.): And 'the ground is full of tiny holes' is only applicable by a fountain, yet the Gemara requires forty Sa'ah in one location? ...

Question (concl): And there it can only be speaking about an article which can be Toveled in less than forty Sa'ah in one go, otherwise no proof would be necessary.

Text: This is also Rashi's text.

Implied Question: Even though the same Din applies to all K'lei Shetef (Keilim other than those made of earthenware) ...

Answer: It nevertheless mentions specifically cushions, covers, sacks and leather commercial-bags, because Rebbi Meir argues specifically with regard to them ...

Source: As we learned in the Seifa 'Rebbi Meir says that whatever has 'Tuvra'os, also has a Din of 'Achorayim and Toch, and whatever does not ... '.

Definition: 'Tuvra'os' are stitches, a rim round the opening (like a pair of trousers), since then it cannot be turned inside out to wear on the other side ...

Definition (cont.): And it has a Din of Achorayim and Toch in that if the back becomes Tamei, the inside does not, like other K'lei Shetef.