The house of the tabernacle: this is added to explain what he means by the house of the Lord; not that tabernacle which David had set up for the ark, but that more solemn tabernacle, which Moses had made by God’s express command and most particular direction; which in David’s time was at Gibeon; in which God was and would be worshipped until the temple was built. See 1Ki_3:22Ch_1:3,5, &c.
By wards, i.e. by turns or courses, each of them at his gate, and in his appointed time.