Jesus will not be demoted to an earthly throne in Jerusalem. He is not ceasing to be a Priest to become a King. For if He were on earth, He should not be a Priest. – Heb 8:4. He is a Priest for ever after to the order of Melchizedek. – Heb7:17. And He will be Priest and King and reign for ever. – Rev 11:15. This is what is signified by prophet Zechariah when the Lord commanded him to place a crowns on the high priest Joshua’s head: Behold the Man whose name is The BRANCH; and He shall grow up out of His place, and He shall build the temple of the LORD: Even He shall build the temple of the LORD; and He shall bear the glory, and shall sit and rule upon His throne; and He shall be a priest upon His throne: and the counsel of peace shall be between them both. – Zech 6:13.

Jesus will not sit on the throne of David (throne of the Lord) on this earth because it is cursed for ever because of Jehoiachin, the second last king of Judah. – Jer 22:28-30. Even after their return to their homeland, Zerubbabel did not sit on the throne as King – he was only the governor of Judea under the Medo-Persian King Darius.