Yoma, Chapter 7, Mishnah 1. After the goat has reached the wilderness, the Mishnah continues its description of the order of the service, and our Mishnah describes the Torah reading of the Kohen Gadol - the reading of the passages that deal with Yom Kippur. The Mishnah opens: "Ba lo kohen gadol likros" - the Kohen Gadol comes to read.
In which garments does he read:
"Im ratzah likros b'vigdei butz - korei" - if the Kohen Gadol wishes to read from the Torah while wearing the white linen garments that are unique to Yom Kippur, he is permitted to do so. He had been wearing these garments earlier, and he had not necessarily removed them by now: even though we learned in the previous chapter that he approached the bull that was to be burned and removed its designated portions, he was not required to change garments before that service. Therefore, if he is still standing in the white garments, he reads in them.
"V'im lav - korei b'itztalis lavan mishelo" - and if he is no longer wearing them, because he already wished to remove the white garments, he may read in a white robe of his own, one that does not belong to the Temple treasury. The white garments of Yom Kippur had to come from the Temple treasury, but this robe may even be his own, since the Torah reading is not part of the service itself. Therefore he is permitted to change into it.
The order in which the Torah scroll is passed along:
In order to enhance the honor of the Kohen Gadol, the Torah scroll passes through a chain of officials, from the lowest rank to the highest:
"Chazan ha'knesses notel sefer Torah" - the chazan of the assembly takes the Torah scroll. The chazan is the one appointed to make certain that everything needed in the Temple is present and prepared. This is the source of the word 'chazan', and although in itself it has nothing to do with leading the prayers, its root means to see - to oversee and supervise all the matters that are required.
"V'nosno l'rosh ha'knesses" - he hands it to the official above him, the head of the assembly, who is the one who determines who will fill each role in the service of the assembly.
"V'rosh ha'knesses nosno la'segan" - and the head of the assembly gives it to the segan, the deputy of the Kohen Gadol.
"V'ha'segan nosno l'chohen gadol" - and the segan gives it to the Kohen Gadol.
"V'chohen gadol omeid u'mekabel v'korei omeid" - he rises to his feet, receives the Torah scroll standing, and reads from it standing.
The Gemara derived from the word "omeid" that until that moment he had been sitting. And since he had been sitting, it is clear that he is not in the Azarah at that time, for no one sits in the Azarah except for the kings of the House of David, so he must be sitting in the Ezras Nashim. In any case, now he rises and begins to read.
The passages that he reads:
"V'korei Acharei Mos" - first he reads the portion of Acharei Mos in the book of Vayikra, which describes the Yom Kippur service.
"V'Ach b'Asor" - afterward he skips ahead to the portion of Emor in the book of Vayikra, which deals with all the festivals, and in which it says, "But on the tenth of this seventh month."
"U'v'Asor shebe'Chumash haPekudim korei al peh" - the passage that begins with "U'v'Asor", which is in the Chumash of the Countings, meaning the book of Bamidbar, in the portion of Pinchas - that one he reads by heart.
And how is this done? "V'golel sefer Torah" - he rolls up the Torah scroll, for a third reading still lies before him, but rolling all the way to the portion of Pinchas in Bamidbar would take far too long. "U'manicho b'cheiko v'omer: Yoser mimah shekarasi lifneichem kasuv kan" - he places the scroll against his chest and announces that everything he is about to read is written in the Torah scroll before him as well. With this announcement he makes clear that he is not reading by heart because of any deficiency in the Torah scroll, but only because rolling to that place would take too much time, and the Torah scroll is complete.
The eight berachos:
"U'mevarech alav shemoneh berachos" - after the reading, the Kohen Gadol recites eight berachos:
"Al haTorah" - the berachah that we recite when we are called up to the Torah.
"V'al ha'avodah" - the berachah of 'Retzeh', concerning the service in the Temple.
"V'al hahoda'ah" - the berachah of 'Modim', giving thanks to Hashem.
"V'al mechilas he'avon" - a special berachah for the forgiveness of sins, which we recite on Yom Kippur.
"V'al haMikdash bifnei atzmo" - a special berachah for the Temple, which concludes with 'Who dwells in Zion'.
"V'al Yisrael bifnei atzmo" - a berachah for the Jewish people on its own, that Hashem not remove His Presence from the Jewish people, and it concludes with 'Who chooses Israel'.
"V'al hakohanim bifnei atzmo" - a berachah for the kohanim, that their offerings be accepted, and it concludes with 'Who sanctifies the kohanim'.
"V'al she'ar hatefillah" - a general berachah for the rest of the prayer, which concludes with 'Blessed are You, Hashem, Who hears prayer'.
In summary: in this Mishnah we learned the order of the Kohen Gadol's Torah reading: the garments in which he reads - the linen garments or a white robe of his own, since the Torah reading is not part of the service itself; the chain by which the Torah scroll is passed from the chazan of the assembly to the head of the assembly, to the segan and to the Kohen Gadol, in order to enhance his honor; his receiving the scroll and reading while standing, from which we learned that he had been sitting in the Ezras Nashim; the three passages - Acharei Mos, "Ach b'Asor" and "U'v'Asor" in the Chumash of the Countings, which is read by heart together with the announcement that the Torah scroll is complete; and the eight berachos that concluded the reading.