2 Chronicles 23:2-4

American Standard Version

² And they went about in Judah, and gathered the Levites out of all the cities of Judah, and the heads of fathers’ houses of Israel, and they came to Jerusalem. ³ And all the assembly made a covenant with the king in the house of God. And he said unto them, Behold, the king’s son shall reign, as Jehovah hath spoken concerning the sons of David. 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;