Ezekiel 42:1, 3, 7-9, 14

Then he brought me forth into the outer court, the way toward the north: and he brought me into the chamber that was over against the separate place, and which was over against the building toward the north.

Over against the twenty cubits which belonged to the inner court, and over against the pavement which belonged to the outer court, was gallery against gallery in the third story.

And the wall that was without by the side of the chambers, toward the outer court before the chambers, the length thereof was fifty cubits. For the length of the chambers that were in the outer court was fifty cubits: and, lo, before the temple were a hundred cubits. And from under these chambers was the entry on the east side, as one goeth into them from the outer court.

When the priests enter in, then shall they not go out of the holy place into the outer court, but there they shall lay their garments wherein they minister; for they are holy: and they shall put on other garments, and shall approach to that which pertaineth to the people.