2 Chronicles 23:2-4

Young's Literal Translation

² And they go round about in Judah, and gather the Levites out of all the cities of Judah, and heads of the fathers of Israel, and come in unto Jerusalem,

³ and all the assembly make a covenant in the house of God with the king, and he saith to them, `Lo, the son of the king doth reign, as Jehovah spake concerning the sons of David.

⁴ `This [is] the thing that ye do: The third of you, going in on the sabbath, of the priests, and of the Levites, [are] for gatekeepers of the thresholds,