Revelation 9:1 And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.
This star that falls from heaven is an angel (Revelation 1:20) because the star is referred to as "him". He was given the key to the bottomless pit, which would have to be a pit shaped like a circle and hollow inside. This circle could in the core of the earth, where it is constantly rotating with the rotation of the earth. This judgment is also a Woe judgment. The first four triumph judgments were against the earth the last three woe judgments are against men. These judgments gives men a sample of what hell is like.

Revelation 9:2 And he opened the bottomless pit; and there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit.
Revelation 9:3 And there came out of the smoke locusts upon the earth: and unto them was given power, as the scorpions of the earth have power.
These are supernatural locusts. They are demoniac monstrous beings that have been in the bottomless pit were the beast has also been.

Revelation 9:4 And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.

We have seen in Revelation 8:7 that all the green grass has already been burned up and one third of all the trees have been burn up. This judgment must have happen at a later date because the grass had time to grow back.

Revelation 9:5 And to them it was given that they should not kill them, but that they should be tormented five months: and their torment was as the torment of a scorpion, when he striketh a man. These are the men that wish to die but can not. Revelation 6:16 And said to the mountains and rocks, Fall on us, and hide us from the face of him that sitteth on the throne, and from the wrath of the Lamb:
The only ones that have been sealed are the 144,000 from each of the 12 tribes of Israel. The event must have happen after the Nation of Israel has been taken down into the wilderness to be protected by God. Revelation 12:6 And the woman fled into the wilderness, where she hath a place prepared of God, that they should feed her there a thousand two hundred and threescore days. The only people left are the ones that have taken the mark of the beast. These men were not killed but they were seeking death because of their torment.

Revelation 9:6 And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them.

Revelation 9:7 And the shapes of the locusts were like unto horses prepared unto battle; and on their heads were as it were crowns like gold, and their faces were as the faces of men.
Revelation 9:8 And they had hair as the hair of women, and their teeth were as the teeth of lions.
Revelation 9:9 And they had breastplates, as it were breastplates of iron; and the sound of their wings was as the sound of chariots of many horses running to battle.
Revelation 9:10 And they had tails like unto scorpions, and there were stings in their tails: and their power was to hurt men five months.
This is not a modern day army and machines. Don't make these locusts any kind of figurative or spiritual interpretation; just believe the words on the page.
John gets carried away in the spirit and gets see these events that are going on during the tribulation period. It is a literal description of demoniac beings because of what follows.

Revelation 9:11: And they had a king over them, which is the angel of the bottomless pit, whose name in the Hebrew tongue is Abaddon, but in the Greek tongue hath his name Apollyon.
The king over them is the king of the bottomless pit. His two names are translated "perdition" in II Thessalonians 2:3 (the son of perdition). He comes up out of the bottomless pit. These locusts are supernatural because the ordinary locusts have no king Proverbs 30:27 The locusts have no king, yet go they forth all of them by bands;

Revelation 9:12 One woe is past; and, behold, there come two woes more hereafter.
Revelation 9:13 And the sixth angel sounded, and I heard a voice from the four horns of the golden altar which is before God,
Revelation 9:14 Saying to the sixth angel which had the trumpet, Loose the four angels which are bound in the great river Euphrates.
Revelation 9:15 And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men.
Revelation 9:16 And the number of the army of the horsemen were two hundred thousand thousand and I heard the number of them.
In Revelation 6:8 a fourth part of men were killed. When the four angels were loosed out of the river Euphrates they killed a third part of the men that were left. The army of the horsemen comes out of the East, which numbered 200 million men. Note the soldiers are on horse back not in modern tanks and airplanes. Could it be that when this happens there will be no modern means of warfare.

Revelation 9:17 And thus I saw the horses in the vision, and them that sat on them, having breastplates of fire, and of jacinth, and brimstone: and the heads of the horses were as the heads of lions; and out of their mouths issued fire and smoke and brimstone.
Revelation 9:18 By these three was the third part of men killed, by the fire, and by the smoke, and by the brimstone, which issued out of their mouths.
Satan is an imitator. These are supernatural horsemen that killed a third part of the men that were left. Remember when the Lord returns at the second coming the armies of heaven follow him. The armies of the Lord are made up of OT saints and all the holy angels. The OT saints also return on white horses (Revelation 19:14).

One fourth of all the people on the earth are killed by the pale horse rider, one third of the people that are left on earth are killed by the four angels that are loosed out of the River Euphrates and one third of the people that are left are killed by the horses that come out of the bottomless pit.

Revelation 9:19 For their power is in their mouth, and in their tails: for their tails were like unto serpents, and had heads, and with them they do hurt.
Revelation 9:20 And the rest of the men which were not killed by these plagues yet repented not of the works of their hands, that they should not worship devils, and idols of gold, and silver, and brass, and stone, and of wood: which neither can see, nor hear, nor walk:
Revelation 9:21 Neither repented they of their murders, nor of their sorceries, nor of their fornication, nor of their thefts.
This army of Satan is the third part of the angels that followed him. There has been a war in heaven and Satan and his angels have been cast out upon the earth when this army kills a third part of the men left on the earth. After all that has happen, the men that are left repent not and still worshipped devils.
Revelation 12:4 And his tail drew the third part of the stars of heaven, and did cast them to the earth: and the dragon stood before the woman which was ready to be delivered, for to devour her child as soon as it was born.
Revelation 12:7 And there was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels,
Revelation 12:8 And prevailed not; neither was their place found any more in heaven.

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