The sixth angel sounded his trumpet, and I heard a voice coming from the four horns of the golden altar that is before God. 14 It said to the sixth angel who had the trumpet, “Release the four angels who are bound at the great river Euphrates.” 15 And the four angels who had been kept ready for this very hour and day and month and year were released to kill a third of mankind. 16 The number of the mounted troops was twice ten thousand times ten thousand. I heard their number. (Revelation 9:13-16)
In the second “woe” a third of mankind will be killed by a great army. Notice that this judgment comes from a command issued at the center of the “four horns of the golden altar that is before God.” Once again we see the judgment of Earth linked to commands issued from the Holy temple in Heaven. This implies that God’s holiness requires this judgment to happen.