If one vowed not to eat a loaf, he may be Me'arev with it. If he was Makdish it, he may not be Me'arev with it.

If one vowed not to eat a loaf, he may be Me'arev with it, for it is proper [for others] to eat it. If he was Makdish it, he may not be Me'arev with it, for he and others may not eat it.

Question (R. Acha): (Why is it not proper for anyone to eat it?) Can one not ask [to permit] his Hekdesh?

Question (R. Acha citing R. Maisha): There, R. Shimon said in the name of Chiyah brei d'Rav, if one made idolatry to be a Lechi for a Mavuy, it permits the Mavuy [even though it is Asur b'Hana'ah]. Here you say so [that one may not be Me'arev with Hekdesh]?!

Answer (R. Elazar): There, in any case the Mavuy is sealed. Here, what do you have?! (An Eruv must be proper to eat. He cannot eat Hekdesh!)

(Beraisa): We may be Me'arev on behalf of a Nazir with wine, for others may drink it; and on behalf of a Yisrael with Terumah, for a Kohen may eat it, and for a Kohen in a Beis ha'Pras.

Assertion: The Beraisa is like Beis Shamai. Beis Shamai say, we are Me'arev for someone only if the Kelim he uses are there. [One might have thought that the Me'arev must be able to go there. The Beraisa permits in a Beis ha'Peras, since the Isur for a Kohen to go there is only mid'Rabanan.]

Consequence: Sumchus holds like Beis Shamai, for our Mishnah teaches that Sumchus says [that one may be Me'arev with] Chulin for a Kohen in a Beis ha'Peras.

Objection (to assertion and consequence): If so, [the Beraisa and Sumchus should permit] even in a cemetery! He can transgress Shevus and eat it, for he can enter in a chest, box or tower and make a hole less than a Tefach [which does not allow Tum'ah inside] and insert a spindle or chip [into the food, and take it into the chest and eat it! (HA'GAON RAV C. KANIEVSKY, SHLITA - the Shevus is taking from the cemetery (Karmelis) to the chest. We explained this mostly like YERUSHALMI KI'PESHUTO.)