Matthew Poole and continuators on 2 Chronicles 31:16

16 Beside their genealogy of males, from three years old and upward , even unto every one that entreth into the house of the LORD , his daily portion for their service in their charges, according to their courses:

To whom a Portion of these things was allotted, as is here implied.

That were capable of entring thither and doing Service there, which they were at twenty years old, as is expressed here, v. 17. & 1 Chron. 23. 24. Through the whole Company of the Priests and Levites.