Twenty and five years old and upward - The permanent limit as distinguished from the temporary Numbers 4:3, Numbers 4:23, Numbers 4:30, though David found it necessary to extend the period of the Levites’ service by causing it to commence at 20 years of age 1 Chronicles 23:24-28. This rule continued in force from the time of David downward (compare on 2 Chronicles 31:17; Ezra 3:8).
Related Commentaries of Numbers 8:24
Numbers 8:24
24 This is it that belongeth unto the Levites: from twenty and five years old and upward they shall go in to wait upon the service of the tabernacle of the congregation: