What is "me'Cheik ha'Aretz"?
Rashi: From the Yesod ? from the ground.
Radak: From the middle of the land and where it is equidistant from Azarah ha'Elyonah and ha'Tachtonah (refer to 43:14:2:3).
What is "Azarah ha'Tachtonah"?
Rashi: It is the top of the first frame [of the Mizbe'ach, i.e. the Yesod]. It is also called Ketanah, for it was only two high; the top one was four high.
Targum Yonasan: Mesamsa. Rashi ? this is an expression of a floor. He filled the frame with smooth rocks, pitch, plaster, and molten lead. He smears, pours and smoothes above; it is like a floor.
Radak: The Mizbe'ach was between them. The place where Kohanim [offering on the Mizbe'ach] stand is called Azarah, just like the place where Yisraelim stand is called Azarah. Elyonah is from the Mizbe'ach towards the Ulam; Tachtonah is from the Mizbe'ach to the east. I do not know which Azarah (Elyon or Tachton) is called Ketanah, and which is Gedolah. In any case, there were four Amos between them. This [four Amos in between] is the place of [the base of] the Mizbe'ach ? "ha'Har'el Arba Amos" (15).
What is the significance of two Amos?
Rashi: It was not so in Bayis [Sheni]. There it was one Amah 1 .
Radak, Abarvenel: From the Mizbe'ach 2 to Azarah ha'Tachtonah was two Amos, i.e. length; "v'Rochav ha'Amah."
Rashi proves that Bayis Sheni was not like it says here. In Zevachim 59b, he was unsure. The Rambam (Hilchos Beis ha'Bechirah 2:3) says that it was exactly the same. Even ha'Ezel (2:3) ? Menachos 97b learns about Bayis Sheni from the verse here! (Perhaps it was known that in all other ways, they were the same. - PF) He can explain our verse like Radak, that Azarah ha'Tachtonah is not the Yesod (refer to 43:14:3:2).
I.e. from the middle of the Mizbe'ach. If it is truly the middle, this is in the middle of the base! Also, what is one Amah wide? Radak and Abarvenel explain that the base was four by four, and past that the Mizbe'ach itself stuck out (four Amos above the ground) several Amos on all sides! Perhaps they discuss a path north of the entire Mizbe'ach (but not on the south, for the ramp was there). The distance from the middle of the Mizbe'ach from east to west was two Amos from each Azarah. Therefore, there were four Amos between the two Azaros. The path between the Azaros, which consists of the two paths from the middle to each of the Azaros, was one Amah wide. Granted, the path does not include what is under the Mizbe'ach (that is over the base and sticks out past it) on the south side. I do not know why the path is only one Amah wide ? was there a step or wall to the north after one Amah? (PF)
Was it only one Amah wide?
Rashi: When the second frame which was 30 by 30, was put on it, it was one Amah recessed from the first frame all around.
Refer to 43:14:3:2 and the note there.
What is "Azarah ha'Gedolah"?
Rashi: It is the roof of the frame on top of the lowest frame (the Yesod).
Targum Yonasan: Mesamsa. Rashi ? this is an expression of a floor. He filled the frame with smooth rocks, pitch, plaster, and molten lead. He smears, pours and smoothes above; it is like a floor.
Was Azarah ha'Gedolah only one Amah wide?
Rashi: Its recession was one Amah recessed from the first frame all around.
Refer to 43:14:3:2 and the note there.