John Gill Commentary 2 Chronicles 31:15

"And under him were Eden, and Miniamin, and Jeshua, and Shemaiah, Amariah, and Shecaniah, in the cities of the priests, in their office of trust, to give to their brethren by courses, as well to the great as to the small:" — 2 Chronicles 31:15 (ASV)

And next to him were Eden and Mijamin, and Jeshua, and
Shemaiah, Amariah, and Shecaniah
As Kore was the principal, and his business lay chiefly with the priests in the temple, and in Jerusalem, these men under him were employed in distributing to the priests.

This distribution was carried out "in the cities of the priests"; that is, in the several parts of the country.

They performed this duty "in their set office"; or faithfully.

Their task was "to give to their brethren by courses", as well to the great as to the small; to communicate of the stores under their hands, according to their several courses, both priests and Levites, and to all in their families, small and great.