His descendants also will I make to endure forever, and his throne as the days of heaven.
Read Chapter 89
Augustine of Hippo
AD 430
28. "His seed will I make to endure world without end" (ver. 29). Not only for this world, but unto the world without end: whither His seed, which is His heritage, the seed of Abraham, which is Christ, will pass. But if ye are Christ's, ye are also Abraham's seed: and if ye are destined His heirs for ever, "He will establish His seed unto world without end: and His throne as the days of Heaven." The thrones of earthly kings are as the days of the earth: different are the days of Heaven from those of earth. The days of Heaven are those years of which it is said, "Thou art the same, and Thy years shall not fail." The days of the earth are soon overtaken by their successors: those which precede are shut out from us: nor do those which succeed remain: but they come that they may go, and are almost gone before they are come. Such are the days of earth. But the days of Heaven, which are also the "One day" of Heaven, and the never failing years, have neither beginning nor end: nor is any day ...
Heaven. This can only be verified in Christ, who rules over all, and gives power to his Church unto the end. The family of David has been confounded with the rest of the nation for nearly 2,000 years. (Calmet)
The temporal dominion of those princes has ceased in Jechonias, (Du Hamel) like that of other monarchs; so that God had in view a different throne, (Berthier; ver. 5.) and the Messias, who would render the kingdom of David perpetual, (Menochius) in a spiritual sense. (Haydock)
