Revelation 9:13-15

Revised Standard Version

¹³ Then the sixth angel blew his trumpet, and I heard a voice from the four horns of the golden altar before God, ¹⁴ saying to the sixth angel who had the trumpet, “Release the four angels who are bound at the great river Euphra′tes.” ¹⁵ So the four angels were released, who had been held ready for the hour, the day, the month, and the year, to kill a third of mankind.