World Wide Study Bible
a Bible passage
22Just as the host of heaven cannot be numbered and the sands of the sea cannot be measured, so I will increase the offspring of my servant David, and the Levites who minister to me.
22. (Ge 15:5; 22:17). The blessing there promised belonged to all the tribes; here it is restricted to the family of David and the tribe of Levi, because it was on these that the welfare of the whole people rested. When the kingdom and priesthood flourish in the person of Messiah, the whole nation shall temporally and spiritually prosper.