1 Chronicles 23:27

from thirty years and upward, even to fifty years old, all who enter the duty of doing the work in the tent of meeting.

from thirty years and upward to fifty years old, you shall number them; all who enter to perform the duty of performing the service in the tent of meeting.

“This is what applies to the Levites: from twenty-five years old and upward they shall enter to perform their duty in the service of the tent of meeting.

And Jehoiada placed the assignments concerning the house of Yahweh in the hand of the Levitical priests, whom David had divided by lot to be over the house of Yahweh, to offer the burnt offerings of Yahweh, as it is written in the law of Moses—with gladness and singing according to the order of David.