John Gill Commentary 1 Chronicles 26:1

"For the courses of the doorkeepers: of the Korahites, Meshelemiah the son of Kore, of the sons of Asaph." — 1 Chronicles 26:1 (ASV)

Concerning the divisions of the porters Or doorkeepers, whose business it was to open and shut the doors of the temple, to keep all impure and improper persons from entering into it, or any of the vessels being carried out of it, and to prevent tumults and riots about it; these, as it seems, David divided into a like number of classes, as the singers, to take their turns in waiting: of the Korhites was Meshelemiah the son of Kore, of the sons of Asaph; not Asaph the singer, who was a Gershonite, but the same with Eliasaph, (1 Chronicles 6:23 1 Chronicles 6:27) a Korhite.