2 Chronicles 17:19
Ver. 19. These waited on the king,.... Not this vast number of men at one time, but in course, as David's military men waited on him, 1Ch 27:1 or each of these captains, with a proper number of men under them detached from the body; and they were all ready to obey the king's orders whenever he should have occasion for them:
besides those whom the king put into the fenced cities throughout Judah; and all together, the militia of the kingdom was very numerous and formidable.
John Gill's Exposition of the Entire Bible.