4 Who shall not fear thee, O Lord, and glorify thy name? for thou only art holy: for all nations shall come and worship before thee; for thy judgments are made manifest.
He expresses here more fully the purpose and goal of the elect, who say from the heart, “Put the way of iniquity far from me, O Lord, and graciously teach me your law,” or, “For the sake of your law I have endured for you, O Lord,” and things similar to these. [By this scene] he wishes to make clear that these are in the number of the faithful in that they are participants in the victory mentioned. In Moses the Old Testament is signified as the New Testament is signified in the Lamb, and by this it teaches us that the elect were all equipped from both and perfected in both.… By a harmonious truth the pages of both Testaments testify to us concerning [their song], for “all the paths of the Lord are mercy and truth.” He is more aptly called the king of the nations, because he was a God not only known among the Jews, nor did the dew from heaven moisten only one fleece. But as Malachi said, “From the rising of the sun to its setting my name is great among the nations, and in every place a pure offering is sacrificed and offered to my name.”
From the song of Moses we learn the hymn sent up to God by those who were justified by the law before [the coming of] grace. From the song of the Lamb we learn the thanksgiving of those who lived in holiness after the coming of the Christ. This thanksgiving is for those benefactions and gifts from him that have come to our race, since through the holy apostles he has called all nations to the knowledge of him.
He says, I saw seven angels with seven plagues. By the number seven he means the many plagues prepared against the sinners, by means of which God’s wrath reaches its limit.
He says, And I saw a sea of glass mingled with fire, and the conquerors of the beast and its image and the number of its name, standing beside the sea of glass holding harps of God. The very wise Paul in one of his writings says, “If anyone builds on this foundation with gold, silver, precious stones, wood, hay, stubble, the quality of each person’s work will be tested by fire, because it will be revealed in fire.” So then when the sinners with their offerings of inflammable loads of sin are put to the test, will the righteous also be tested in fire although they bring along gold and their precious materials?
He is now speaking of those who have conquered the beast through thick and thin: they are standing beside the sea of glass mingled with fire —glass because of the brightness and purity of the righteous in it, but mixed with fire because of the purging and cleansing of all uncleanness, since even the righteous need to be cleansed. “For we all frequently stumble,” as Scripture says, “and who will be free from uncleanness? no one, not even if their life on earth is but one day.”
The harps, as has often been said, symbolize the tuneful song of the saints addressed to God.
He says, And they sing the song of Moses in its entirety. This was the one he sang when Pharaoh and all his army had been drowned, saying, “Let us sing to the Lord, for he has triumphed gloriously; the horse and his rider he has thrown into the sea; he has become my help and protector for our deliverance.” The song is a paean of victory for the punishment of the ungodly and the victory over the Devil and his lawless son, the Antichrist.
He says, And the song of the Lamb, that is, the appropriate song for the Lord and his righteous judgment against the ungodly; that is why they wonder at the truth and righteousness of the Lord.
He says, The king of the nations: Christ is king of all, but since it is said by Isaiah, “And there will be the root of Jesse and one set up to rule over the nations; on him shall the nations hope,” on account of this the divine oracle says both that he is king of the nations and that all the nations will come and worship him, neatly foretelling the calling of the nations and their faith in the Lord.
[AD 560] Primasius of Hadrumetum on Revelation 15:3-4