2 Chronicles 23:4-6

American Standard Version

⁴ This is the thing that ye shall do: a third part of you, that come in on the sabbath, of the priests and of the Levites, shall be porters of the thresholds; ⁵ and a third part shall be at the king’s house; and a third part at the gate of the foundation: and all the people shall be in the courts of the house of Jehovah. ⁶ But let none come into the house of Jehovah, save the priests, and they that minister of the Levites; they shall come in, for they are holy: but all the people shall keep the charge of Jehovah.