For unto us a Child is born, to us a Son is given and the government shall be upon His shoulder, and His name shall be called Wonderful Counselor, Mighty God, everlasting Father, Prince of Peace; of the increase of His government and of peace there shall be no end; upon the throne of David and over his kingdom, to establish it and to uphold it with justice and with righteousness from the [latter] time forth, even forevermore. The zeal of the Lord of hosts will perform this (Isaiah 9:6-7).
Dr. Arnold Fruchtenbaum, in his book the Footstep of the Messiah, clearly explains to us the meaning of this prophecy: The eternity of the Davidic dynasty throne, and kingdom is assured; it rests in the God-Man. As to His humanity, He is descendant of David; as to His deity, He is eternal and so is His throne. His government will be characterized by justice and righteousness forever. In Jeremiah’s prophecy similar to that of Isaiah, he says: Behold, the days are coming, says the Lord, when I will raise up to David a righteous Branch, and He will reign as King and do wisely and will execute justice and righteousness in the land (Jer. 23:5). YAHSHUA’S throne will be established in Jerusalem, but His reign will extend over the entire earth. YAHSHUA will be considered as one God by the entire earth. The beginning of His reign will be marked by a procession of the King into the millennial Jerusalem described in Psalm 24:7-8: Lift up your heads, O you gates; and be lifted up, you age-abiding doors, that the King of glory may come in. Who is the King of glory? The Lord strong and mighty, the Lord mighty in battle.
There will be a Gentile branch in His millennium kingdom consistent of His church. Revelation 20:4 John writes, Then I saw thrones, and sitting on them were those to whom authority to act as judges and to pass sentence was entrusted. Also, I saw the souls of those who had been slain with axes for their witnessing to YAHSHUA and for the Word of God, and who had refused to pay homage to the beast or his statue and had not accepted his mark or permitted it to be stamped on their foreheads or on their hands. And they lived again and ruled with Messiah a thousand years. The chain of command will be from Messiah to the church and the tribulation saints to the kings of the Gentile nations. In the millennium time there will be earthly kings, but YAHSHUA will be over all of them. He will be King of kings and Lord of lords. The Jewish branch will be through David, as Jeremiah and Ezekiel so described: But they will serve their God and David’s their King, whom I will raise up for them (Jer. 30:9); and I will raise up over them one Shepherd and He shall feed them, even My Servant David; He shall feed them and He shall be their Shepherd and the Lord will be their God and My Servant David a Prince among them; I the Lord have spoken it (Eze. 34: 23-24). (Fruchtenbaum- The Footsteps of the Messiah)