They and their descendants were assigned to guard the gates of the LORD’s sanctuary(that is, the tabernacle).
TSK
TSK · 2 Chronicles 23:19
Treasury of Scripture Knowledge references in NET.
As his father David had decreed, Solomon appointed the divisions of the priests to do their assigned tasks, the Levitical orders to lead worship and help the priests with their daily tasks, and the divisions of the gatekeepers to serve at their assigned gates. This was what David the man of God had ordered.