2 Chronicles 23:2-4

King James Version

² And they went about in Judah, and gathered the Levites out of all the cities of Judah, and the chief of the fathers of Israel, and they came to Jerusalem.

³ And all the congregation made a covenant with the king in the house of God. And he said unto them, Behold, the king's son shall reign, as the Lord hath said of the sons of David.

⁴ This is the thing that ye shall do; A third part of you entering on the sabbath, of the priests and of the Levites, shall be porters of the doors;