Treasury of Scripture Knowledge
From the son of thirty years and above, and to the son of fifty years, all coming in to war to do the works of the tent of appointment
This is that to the Levites: from the son of five and twenty years and above, and he came in to war the warfare in serving the tent of appointment
1 Chronicles 23:3
And the Levites will be numbered from the son of thirty years and above: and their number, for their craniums, for the men, thirty and eight thousand.
1 Chronicles 28:13
And for the divisions of the priests and the Levites, and for all the work of the service of the house of Jehovah, and for all the vessels of the service of the house of Jehovah.
And Jesus himself was beginning about thirty years, being, as was thought, the son of Joseph, of Eli,
1 Timothy 3:6
Not newly planted, lest rendered proud he fall into condemnation of the accuser.