Revelation 9:14
saying to the sixth angel who had the trumpet, "Release the four angels who are bound at the great river Euphrates."
Revelation 16:12
The sixth angel poured out his bowl on the great river Euphrates, and its water was dried up, to prepare the way for the kings from the East.
Revelation 7:1
After this I saw four angels standing at the four corners of the earth, holding back the four winds of the earth, that no wind would blow on the earth or the sea or on any tree.
Revelation 8:2
And I saw the seven angels who stand before God, and to them were given seven trumpets.
Revelation 8:6
The seven angels who had the seven trumpets prepared to sound them.
Revelation 9:15
And the four angels, who had been held ready for the hour and day and month and year, were released to kill a third of mankind.