(Rava): Since the fifth stringency is because of Chatzitzah, it must be that the first one is for another reason.

Rather, the first one is a Gezeirah in order to prevent one from immersing small utensils (needles and weaving-forks) in a vessel whose mouth is smaller than the reed inserted into the mouth of a leather canteen.

(Mikva'os 6:7) A reed, whose hollow is a diameter of two fingers, is the minimum size necessary for the passage of water to be considered linked to, and part of, the Mikvah.

Rava holds like R. Nachman who said in the name of Rabah bar Avuha: There are eleven stringencies in our Mishnah (since the first and the fifth are indeed different cases).

Question: What is the difference between R. Ila's reason and Rava's reason?

Answer: Immersing utensils inside of a Sal or Gargusani (a very wide-mouthed basket) is the difference.

Rava permits it (since there is no fear that the mouth of the outer vessel will be too small).

R. Ila prohibits it (since there is still a problem of the inner utensil weighing down upon the outer utensil, being a Chatzitzah.

This Machlokes between Rava and R. Ila is actually a Machlokes between Tana'im, as recorded in a Beraisa.

The Tana Kama holds like Rava.

Aba Shaul holds like R. Ila.

Question: If this is the reason (R. Ila or Rava) not to immerse utensils inside of utensils for Kodesh, then the same should apply for Terumah and it should be prohibited!

Answer: The Mishnah is speaking to Chaverim (who follow the laws of Tum'ah and Taharah), who will be careful when immersing a utensil within another utensil for Terumah, and will do it correctly.

Even though an Am ha'Aretz might see the Chaver immersing a utensil within another utensil and he will go and do it incorrectly, we do not care, because we do not accept Terumah from an Am ha'Aretz.

Kodesh, though, we must accept from an Am ha'Aretz, because if we do not, it will cause enmity.

Therefore, a Chaver may not immerse a utensil within another utensil for Kodesh, because an Am ha'Aretz might see and do the same (but do it incorrectly), and the Kodesh will be Tamei.

We find in a Beraisa that it is R. Yosi who is concerned for causing enmity.

Question: How can we permit immersing this way for Terumah -- perhaps a Chaver will borrow the utensil from an Am ha'Aretz (and it will be Tamei)!

A Mishnah (Kelim 10:1) (in which Beis Shamai and Beis Hillel argue whether an earthenware vessel of an Am ha'Aretz is able to stop Tum'ah from spreading from one room to another) shows that Chaverim indeed borrow utensils from Amei ha'Aretz!

Answer: When a Chaver borrows a utensil from an Am ha'Aretz, he immerses it again (in case the Am ha'Aretz had immersed it inside another utensil).

Question: But a Beraisa says that an Am ha'Aretz is trusted when he says he immersed properly (for Tum'as Mes)!

Answer #1 (Abaye): That is only for Tevilah of his body, but not for Tevilah of a utensil.

This refers to the Tevilah at the end of his seven day Taharah period (when he had Haza'ah in front of us on both the third and seventh days).

Since we were stringent upon him at the beginning (requiring that he wait three days in front of us before doing Haza'ah, and not trusting him that he counted three days already), we were lenient at the end (believing him when he said he did Tevilah).

Answer #2 (Rava): He is believed for Tevilah of a utensil, but only when he says he never immersed a utensil within another utensil.

But if he says that he has immersed a utensil within another utensil, we do not trust that his Tevilah was valid.

A utensil (used for Terumah) which became Tamei (mid'Rabanan) on the outside, is only Tamei on the outside.

The utensil's thick upper edge and handle remain Tahor.

If it became Tamei on the inside, though, the entire utensil becomes Tamei.

What is the "Beis ha'Tzevitah?"

(Shmuel): The place one holds to stretch it out.

(R. Yochanan): The place on the utensil for dipping.

(R. Bivi): Utensils used for Kodesh become Tamei completely, no matter which part of the utensil was touched by Tum'ah; the same applies to utensils used for Chulin which was prepared with Taharah of Kodesh.

This is consistent with the statement of Rabah bar Avuha.

Rabah bar Avuha said that the first six stringencies in the Mishnah apply both to Kodesh and to Chulin that was prepared with Taharah of Kodesh.