Revelation 9:15
King James Version
“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.”
Context
12One woe is past; behold, there come two woes more hereafter.
13And the sixth angel sounded, and I heard a voice from the four horns of the golden altar which is before God,
14Saying to the sixth angel which had the trumpet, Loose the four angels which are bound in the great river Euphrates.
15And 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.
16And the number of the army of the horsemen two hundred thousand thousand: and I heard the number of them.
17And 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 as the heads of lions; and out of their mouths issued fire and smoke and brimstone.
18By 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.