1 Chronicles 23:3

Now the Levites were numbered from the age of thirty years and upward. The thing which Joab had rightly resisted ( 1 Chronicles 21:3-6 ) and shrunk from doing was now rightly done. There was now a practical and a legitimate object for doing it. This consideration helps to determine what it was that "displeased the Lord" in the former general census of David. In connection with this clause, 1 Chronicles 27:23 should be noted, where we read, "But David took not the number of them from twenty years old and under: because the Lord had said he would increase Israel like to the stars of the heavens." The period from the age of thirty years up to fifty ( Numbers 4:3 , Numbers 4:23 , Numbers 4:35 , Numbers 4:39 ) was fixed under Moses, for those "that came to do the service of the ministry, and the service of the burden in the tabernacle of the congregation" ( Numbers 4:47 ). It is not certain, however, that this census did not inquire, in point of fact, respecting some below this limit of age. For we may note 1 Chronicles 27:24 in the first place, and this is partly explained by Numbers 8:23-25 . The number "thirty and eight thousand" of our present verse may be compared with the "eight thousand and five hundred and four score" of Numbers 4:47 , Numbers 4:48 . It is to be observed how promptly the national council did on this occasion commence with the arrangement of the ministers of religion, "the Levites." As we read ( Numbers 4:3 ) of "thirty years" of age as the appointed age for the commencement of their ministry, and ( Numbers 7:3 ) of the present or "offering" of "six covered waggons and twelve oxen," which the twelve "princes of Israel, heads of the house of their fathers, princes of the tribes," offered "before the Lord," which greatly lessened the laborious work of the Levites; so we find the commencing age reduced from time to time, to "twenty-five" years ( Numbers 8:24 ), and to "twenty years" of age, as in our present chapter ( Numbers 4:24-28 ).