King James Version (KJV)
His seed also will I make to endure for ever, and his throne as the days of heaven.
Modern English
I will establish his offspring forever and his throne as the days of the heavens.
Hebrew
וְשַׂמְתִּ֣י לָעַ֣ד זַרְע֑וֹ וְ֝כִסְא֗וֹ כִּ֣ימֵי שָׁמָֽיִם׃
vshamtiy laʿad zarʿvo vkisʾvo kiymey shamayim