2 Chronicles 23:4-6

Amplified Bible

⁴ This is what you shall do: a third of you, of the priests and Levites who are resuming service on the Sabbath, shall be gatekeepers, ⁵ a [second] third shall be at the king’s house (palace), and a [final] third at the Gate of the Foundation; and all the people shall be in the courtyards of the house of the Lord. ⁶ But let no one enter the house (temple) of the Lord except the priests and the Levites who minister; they may enter, for they are holy. And let all the people carefully observe the law of the Lord.