Commentary - Revelation 9:13-21

Bird's-eye view

In this second woe, following the demonic locusts of the fifth trumpet, the judgment upon apostate Jerusalem intensifies dramatically. The imagery shifts from torment to outright slaughter. A voice from the very center of heavenly worship, the golden altar, commands the release of a devastating force long held in check at the Euphrates. This is not some random alien invasion from a distant galaxy; it is a covenantal judgment rooted in Old Testament geography and prophetic warnings. The Euphrates was the traditional boundary from which God's covenantal curses, in the form of invading armies like Assyria and Babylon, would come. Now, in the first century, a far greater judgment is unleashed upon the generation that rejected the Messiah.

The description of the invading army is terrifying and overtly demonic, emphasizing the spiritual reality behind the physical carnage of the Roman-Jewish War. The number of the army is symbolic of its overwhelming and seemingly infinite size. The fire, smoke, and brimstone recall the destruction of Sodom and Gomorrah, another instance of God's total judgment on a wicked society. A third of mankind is killed, a symbolic fraction representing a massive, catastrophic, but not total, destruction. Yet, the most chilling part of the passage is the conclusion. Despite this horrific divine visitation, the survivors do not repent. Their hearts are so hardened in their idolatry and sin that even a preview of hell on earth does not bring them to their knees. This final impenitence is the ultimate justification for the full measure of wrath that fell upon that generation in A.D. 70.

Outline

Context In Revelation

The sixth trumpet is the second of the three great "woes" that constitute the final trumpet judgments (Rev 8:13). The trumpets, like the seals before them, are not a simple chronological sequence of future events. Rather, they are a recapitulation, a telling of the same story of judgment on first-century Jerusalem from a different angle, with escalating intensity. The seals depicted the internal decay and societal breakdown leading up to the end of the old covenant age. The trumpets depict the active judgments of God, His declaration of war against the apostate city. The fifth trumpet unleashed a demonic torment; this sixth trumpet unleashes a demonic slaughter. This section provides the spiritual backstory for the military campaigns of the Romans under Vespasian and Titus, which culminated in the destruction of the Temple. The unrepentant spirit described at the end of this passage (vv. 20-21) is the very reason for the finality of the judgment that follows.

Key Issues

The Altar and the Euphrates

The action begins with a voice from the golden altar of incense (Rev 9:13). This is the same location from which the prayers of the saints ascended, crying out for vindication (Rev 6:9-10; 8:3-5). The judgment that is about to be unleashed is therefore a direct answer to those prayers. It is not arbitrary violence; it is the settled justice of God, responding to the pleas of His persecuted people. The command is to release angels bound at the "great river Euphrates." In the Old Testament, the Euphrates was the northern border of the promised land at its greatest extent (Gen 15:18). More significantly, it was the geographical staging ground for the great empires, Assyria and Babylon, that God used to bring covenantal judgment upon a faithless Israel. For a first-century Jew hearing this, the Euphrates meant one thing: invasion and destruction from the east. While Rome was geographically to the west, its legions that destroyed Jerusalem came from the eastern provinces, crossing the Euphrates. The symbol points not to a literal river crossing, but to the source of covenantal devastation.

Verse by Verse Commentary

13 Then the sixth angel sounded, and I heard a voice from the four horns of the golden altar which is before God, 14 one saying to the sixth angel who had the trumpet, “Release the four angels who have been bound at the great river Euphrates.”

The sixth trumpet blast initiates the second woe. The command comes not from the angel, but from a singular voice emanating from the four horns of the golden altar. The horns of the altar were where the blood of atonement was applied; they were a place of ultimate sanctity and power. This voice is the voice of God, answering the prayers of the martyrs that have been symbolically collected on that very altar. The judgment is liturgical; it flows from the center of worship. The command is to release four angels. In Scripture, four is often the number of the earth, of worldwide or comprehensive action. These are not good angels, but bound angels, held in check by God's sovereignty until the appointed time. Their location at the Euphrates marks them as agents of covenantal judgment, the instruments of God's wrath against His unfaithful people, just as Assyria and Babylon were in centuries past.

15 And the four angels were released, who had been prepared for the hour and day and month and year, so that they would kill a third of mankind.

God's sovereignty is absolute. These destructive forces were not just bound; they were prepared for a precise moment in time. The cascading phrase "hour and day and month and year" emphasizes the meticulous, down-to-the-second control that God has over the timetable of judgment. History is not a chaotic series of accidents; it is the unfolding of a divine script. Their purpose is explicit: to "kill a third of mankind." As with the other fractions in Revelation, a "third" is not a literal statistic. It represents a massive, devastating, but limited judgment. It is not the final judgment of all men, but a catastrophic judgment upon the "world" of apostate Judaism, the land of Israel. Josephus tells us of the staggering loss of life in the Jewish War, and this is the apocalyptic description of that reality.

16 And the number of the armies of the horsemen was two hundred million; I heard the number of them.

John hears the number, emphasizing that this is a revealed truth, not a human estimate. The number itself, "two hundred million" (literally two myriads of myriads), is symbolic. A myriad was ten thousand, the largest single numerical unit in Greek. This is that number squared and multiplied by two. The point is not a literal headcount, which would have been an impossible number for any army in the ancient world. The point is to convey an image of an overwhelmingly vast, innumerable, and terrifying force. This is the spiritual reality behind the Roman legions that swarmed over Judea, a demonic host of unimaginable size, unleashed to execute God's wrath.

17 And this is how I saw in the vision the horses and those who sit on them: the riders had breastplates the color of fire and of hyacinth and of brimstone; and the heads of the horses are like the heads of lions; and out of their mouths come fire and smoke and brimstone.

John now describes the appearance of this demonic cavalry. The description is not meant to be a zoological report, but a theological one. The colors of the breastplates, fiery red, smoky blue (hyacinth), and sulfurous yellow (brimstone), are the colors of hell itself. These are the very elements that will constitute the lake of fire. The horses are not normal beasts; their heads are like lions, the apex predator, symbolizing ferocious, irresistible power. And their weaponry is supernatural: fire, smoke, and brimstone issue from their mouths. This is the language of Sodom and Gomorrah (Gen 19:24) and of final judgment. This army is a literal hell on earth, a manifestation of the very wrath of God.

18 A third of mankind was killed by these three plagues, by the fire and the smoke and the brimstone which came out of their mouths.

The cause of death is made explicit. The slaughter is accomplished by these three "plagues," a word that directly connects this judgment to the plagues on Egypt. Israel, having rejected her Messiah, had become the new Egypt, and so she receives the judgment of Egypt. The death comes from the mouths of the horses, indicating that this is a judgment that proceeds from the very Word of God. What comes from the mouth is a declaration, a sentence. This demonic army is simply the executioner of a verdict already rendered in the heavenly court.

19 For the power of the horses is in their mouths and in their tails; for their tails are like serpents, having heads, and with them they do harm.

The source of their destructive power is twofold. It is in their mouths, as we have seen, which speaks of their open, lion-like ferocity. But it is also in their tails, which are like serpents with heads. This points to a different kind of harm: deception, treachery, and the venomous sting of false doctrine. The serpent, of course, takes us back to the Garden and to Satan, the original deceiver. This army does not just kill the body; it harms with lies. This was certainly true of the spiritual state of first-century Jerusalem, which was filled with warring factions, false messiahs, and deceitful prophets, all leading the people to their doom. The judgment was both a physical slaughter and a spiritual poisoning.

20 And the rest of mankind, who were not killed by these plagues, did not repent of the works of their hands, so as not to worship demons, and the idols of gold and of silver and of brass and of stone and of wood, which can neither see nor hear nor walk.

This is, in many ways, the most terrifying verse in the chapter. One might think that such a cataclysmic and obvious display of divine wrath would bring the survivors to their knees. But it does not. They remain utterly impenitent. John identifies the root of their sin as idolatry, the "works of their hands." While the first-century Jews were not bowing to literal statues of Baal as their ancestors had, they had created their own idols: a racialized conception of salvation, a trust in the Temple as a talisman, a legalistic system of self-righteousness. Behind all false worship lie demons. Paul says that what the pagans sacrifice they offer to demons (1 Cor 10:20). John makes the same connection here. Their worship was demonic at its root. And like the idols they served, they had become spiritually blind, deaf, and immobile, unable to see God's hand, hear His warning, or walk in His ways.

21 And they did not repent of their murders nor of their sorceries nor of their sexual immorality nor of their thefts.

The idolatry of the heart manifested itself in a torrent of ethical filth. John lists four categories of sin that characterized this unrepentant generation. Murders: not just the killing of the prophets of old, but the murder of the Messiah Himself and the persecution of His followers. Sorceries: the Greek word is pharmakeia, from which we get "pharmacy." It refers to the use of drugs in connection with occult practices, a deep-seated rebellion against God's created order. Sexual immorality: the Greek is porneia, a catch-all term for all sexual sin outside of biblical marriage, which was rampant. And thefts: the greed and exploitation that Jesus condemned in the Temple leadership. This is a portrait of a society that has come completely unglued from its covenantal moorings. Their refusal to repent in the face of overwhelming judgment was the final seal on their doom.

Application

The sixth trumpet is a stark reminder that God's patience has a limit. There is a point at which judgment becomes inevitable, and when it comes, it is terrifying and just. But the central application for us is found in the final two verses. The greatest horror is not the demonic cavalry, but the hardness of the human heart that refuses to repent even when hell is breaking loose all around.

We must examine our own hearts. What are the "works of our hands" that we trust in? What are the idols of gold, silver, brass, stone, and wood that we have fashioned for ourselves? They may not be statues in a shrine, but they are just as real. They are the idols of career, comfort, reputation, political power, and personal autonomy. We worship these things, and in so doing, we are trafficking with demons. And this internal idolatry will always, always manifest itself in external sin, in greed, in lust, in bitterness, in deceit.

The only escape from this judgment is the repentance that the men in this passage refused. But we must understand that repentance is not something we can gin up on our own. It is a gift of God's grace. We are just as blind, deaf, and dead in our sins as they were. Our only hope is that God, by His sovereign Spirit, would grant us a new heart, a heart that is horrified by its own sin and that flees for refuge to the cross of Jesus Christ. The fire, smoke, and brimstone that this passage describes is what Jesus endured on our behalf. He drank the cup of God's wrath so that we would not have to. The call of the gospel is to turn from our dead idols and our wicked deeds, and to trust in Him alone. For those who do, the trumpet is not a sound of woe, but the blessed sound of the coming of our King.