Apocalypse Revealed #412
412. Then the fourth angel sounded. (8:12) This symbolizes an examination and disclosure of the state of the church in people for whom religion is faith alone, that they are caught up in the evils accompanying falsity and in the falsities accompanying evil.
That this is the symbolic meaning follows from what follows next, understood in the spiritual sense.
To sound a trumpet here means, symbolically, to examine and expose, as in nos. 398, 402, and 407, above.
Joshua 10:12-13
12
Then Joshua spoke to Yahweh in the day when Yahweh delivered up the Amorites before the children of Israel; and he said in the sight of Israel, "Sun, stand still on Gibeon! You, moon, stop in the valley of Aijalon!"
13
The sun stood still, and the moon stayed, until the nation had avenged themselves of their enemies. Isn't this written in the book of Jashar? The sun stayed in the midst of the sky, and didn't hurry to go down about a whole day.