Ezekiel 42:18 (KJV)

Then said he unto me, The north chambers and the south chambers, which are before the separate place, they be holy chambers, where the priests that approach unto the LORD shall eat the most holy things: there shall they lay the most holy things, and the meat offering, and the sin offering, and the trespass offering; for the place is holy.

When the priests enter therein, then shall they not go out of the holy place into the utter court, but there they shall lay their garments wherein they minister; for they are holy; and shall put on other garments, and shall approach to those things which are for the people.

Now when he had made an end of measuring the inner house, he brought me forth toward the gate whose prospect is toward the east, and measured it round about.

He measured the east side with the measuring reed, five hundred reeds, with the measuring reed round about.

He measured the north side, five hundred reeds, with the measuring reed round about.

He turned about to the west side, and measured five hundred reeds with the measuring reed.

He measured it by the four sides: it had a wall round about, five hundred reeds long, and five hundred broad, to make a separation between the sanctuary and the profane place.