(Mishnah): If one separates flour to be Chalah, it is not Chalah, and it is theft in the Kohen's hand.

The dough itself (from which flour was taken for Chalah) is obligated in Chalah, and the flour, if it has a Shi'ur [and one will make a dough from it] is obligated in Chalah and it is forbidden to Zarim. R. Yehoshua says so;

Rabanan (to R. Yehoshua): A case occurred, and a Chacham Zar grabbed [and ate] it!

R. Yehoshua: He ruined himself (transgressed), and fixed others (this will be explained).

Five Reva'im of flour are obligated in Chalah - they and their Se'or and their fine bran and their coarse bran are obligated;

If one removed their coarse bran (to make clean bread) and returned it [to the dough, and this completed the Shi'ur], they are exempt.

The Shi'ur of Chalah (that one must separate) is one part in 24 [of the dough].

If one makes a dough for himself, or makes for his son's nuptial feast, [the Shi'ur is] one part in 24;

If a baker makes [dough] to sell in the market, and also a woman who makes to sell in the market, [the Shi'ur is] one part in 48;

If the dough became Tamei b'Shogeg or through Ones, [the Shi'ur is] one part in 48. If it became Tamei b'Mezid, one part in 24, lest a sinner profit (take less Chalah).

R. Eliezer says, one may take from Tahor [dough] on Tamei.

How is this? A Tahor dough and a Tamei dough - he takes the amount for Chalah from a dough from which Chalah was not taken, and puts less than k'Beitzah (the Shi'ur for Tum'ah) in the middle, in order that he will take Min ha'Mukaf;

Chachamim forbid [to do so].

(Gemara - Mishnah - R. Yehoshua: He ruined himself, and fixed others.

He ruined himself - he ate it, and was punished. He fixed others - they eat what is fixed. (They learned from him that one who separated flour did not do anything, and dough must be taken for Chalah. He was punished, for Rabanan forbade the flour to Zarim.)

Some teach that he fixed himself, and ruined others.

He fixed himself, for in any case he ate it. He ruined others - they inferred that [the flour] is exempt [even if it has a Shi'ur Chalah. Really, then] it is obligated! (PF) (I.e. this opinion explains 'if it has a Shi'ur, it is obligated in Chalah and it, i.e. the Chalah taken from the flour, is forbidden to Zarim.' RI KORKUS (Hilchos Bikurim 8:1) - the RAMBAM explained our Mishnah like this, for he had our text 'Asurah' (feminine); if the Kemach were forbidden, it would say 'Asur'. The flour is always permitted to Zarim. The Meforshim's Perush is difficult. Is eating Isur b'Mezid a Tikun for himself?! And if it is, why is it Kilkul for others to eat b'Shogeg?)

Note: According to my Perush, what was Chachamim's challenge from this episode? Perhaps there was a Shi'ur of Chalah, and the text should say 'Tiken l'Atzmo mi'Makom Acher v'Achlah...' (It was written abbreviated Mem Mem Aleph, and a scribe did not understand, so he omitted the Aleph.) I.e. he declared Chalah (on the dough from this flour) to be from another dough. Onlookers did not know this, and thought that he ate without any declaration. It is better if this was Chalas Chutz la'Aretz, which need not be separated Min ha'Mukaf.

(R. Imi citing R. Yanai): A Kav of Tiverya is obligated in Chalah.

A Chalitar (one who makes Chalitah in a pan, i.e. boiling water is poured on the flour) asked R. Yochanan [how to exempt it, for it is not clear which Chalitah is exempt]. He said, make [each dough] four and a half [Reva'im].

Question: He should have told him to make [each] three and a half! (R. Yochanan was in Tiverya. There, four Reva'im (a Kav) is obligated!)

Answer (R. Ze'ira): The Kav in [R. Yochanan's] place (Tiverya) became a quarter smaller (it became like a Kav of Tzipori; only five Reva'im are obligated. We explained this like SHA'AREI TORAS ERETZ YISRAEL.)

Question: He should have told him five [Reva'im] less a small amount!

Answer: He should not come to a Safek Chiyuv Chalah (if he errs, and it is really a full five Reva'im).

(R. Yochanan): [If one removed their coarse bran and returned it, our Mishnah exempts,] for we learned [that the Chiyuv Chalah is for] the normal way of making a dough.

(Reish Lakish): [Our Mishnah] is like R. Shimon ben Gamliel, for R. Shimon ben Gamliel says, it is never obligated in Chalah until there is a Shi'ur of grain. (Once bran was separated, it is not considered grain.)

(Talmidim of R. Chiya bar Ba citing R. Liliani citing R. Yehoshua ben Levi): [Our Mishnah] is like everyone.

(R. Mana): Even though R. Yochanan did not say this [explicitly], he said like it;

(R. Yochanan): We learned [that the Chiyuv Chalah is for] the normal way of making a dough.

Here, since he removed their coarse bran and returned it to it, this is not the way of a dough (so all exempt).