It reads in Psalm 72:11 KJV:
Yea, all kings shall fall down before him: all nations shall serve him.

Or worship him; not with a civil, but religious worship; for such worship is due to Christ, he being God equal with the Father, and so to be equally honored; the Creator of all things, the Redeemer of his people, Head and Lord of the church, and whom the angels adore; every part of worship is to be given him; internal, which lies in the exercise of faith, hope, love, fear and external, which consists of prayer to him, praise of him, preaching in his name, and the administration of ordinances; and this worship is to be performed in the same manner as to the Father, in spirit and in truth, in righteousness and holiness, with reverence and godly fear. This is to be understood, either literally of the kings of the earth, and which will have its full accomplishment in the latter day; see (Isaiah 49:23, Kings will be your foster fathers, and their queens your nursing mothers. They will bow down before you with their faces to the ground; they will lick the dust at your feet. Then you will know that I am the LORD; those who hope in me will not be disappointed.”) (Isaiah 60:3, Nations will come to your light, and kings to the brightness of your dawn.) (Isaiah 60:11, Your gates will always stand open, they will never be shut, day or night, so that people may bring you the wealth of the nations, their kings led in triumphal procession.) (Isaiah 60:16, You will drink the milk of nations and be nursed at royal breasts. Then you will know that I, the LORD, am your Savior, your Redeemer, the Mighty One of Jacob. ) ; or mystically of such who are made kings unto God the Father by Christ; who reign spiritually now, through the power of divine grace in their hearts; have the Honor, riches, and attendance of kings, and a crown and kingdom prepared for them; and shall reign with Christ on earth, though under him, at whose feet they cast their crowns: all this shows the dignity of Christ’s person and office; that he is the Prince of the kings of the earth, the firstborn of God, whom he has made higher than they, and King of kings, and Lord of lords; whose princes, and all whose subjects, are altogether kings. This passage is allowed to belong to the Messiah, both by ancient and modern Jews; and indeed, it never was true of Solomon, nor of any other.

all nations shall serve him.
which will be in the latter day; see (Isaiah 2:2, In the last days the mountain of the LORD’s temple will be established as the highest of the mountains; it will be exalted above the hills, and all nations will stream to it.) (Revelation 11:15, The seventh angel sounded his trumpet, and there were loud voices in heaven, which said: “The kingdom of the world has become the kingdom of our Lord and of his Messiah, and he will reign for ever and ever.”) (Revelation 15:4, Who will not fear you, Lord, and bring glory to your name? For you alone are holy. All nations will come and worship before you, for your righteous acts have been revealed.”15:4) the Jews say, that in the world to come, or the times of the Messiah, all the Gentiles shall be voluntary proselytes