“And the sixth angel sounded, and I heard a voice from the four horns of the golden altar which is before God,”
King James Version (KJV)
9:13 And the sixth angel sounded - Under this angel goes forth the second woe. And I heard a voice from the four corners of the golden altar - This golden altar is the heavenly pattern of the Levitical altar of incense. This voice signified that the execution of the wrath of God, mentioned verses 20, 21, #Rev 9:20|,21 should, at no intercession, be delayed any longer.
Re 9:13 THE SIXTH TRUMPET. I heard a voice from the four horns of the golden altar. A voice is then heard coming from the golden altar of incense. See Re 8:3. He does not say who spoke, but declares the command uttered.