Numbers 4:3

3 afrom thirty years old up to fifty years old, all who can come on duty, to do the work in the tent of meeting.

Numbers 28:24

24In the same way you shall offer daily, for seven days, the food of a food offering, with a pleasing aroma to the Lord. It shall be offered besides the regular burnt offering and its drink offering.

1 Chronicles 23:24

24 bThese were the sons of Levi by their fathershouses, the heads of fathers’ houses cas they were listed according to the number of the names of the individuals from dtwenty years old and upward who were to do the work for the service of the house of the Lord.
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