Charles Ellicott Commentary Revelation 8:12

"And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; that the third part of them should be darkened, and the day should not shine for the third part of it, and the night in like manner." — Revelation 8:12 (ASV)

And the fourth angel . . .—Translate: And the fourth angel sounded, and the third part of the sun was struck, and the third part of the moon, and the third part of the stars; so that the third part of them would be darkened, and the day would not shine for its third part, and the night likewise.

The dimness that thus falls on the lights of heaven carries us back to the plague of darkness (Exodus 10:21–23); yet there is this difference: in that plague, the children of Israel had light in their dwellings while all the rest of the land suffered the darkness that might be felt. Here, however, the darkness is only such as results from the withdrawal of a third of the light of the sun by day, and of the moon and the stars (so much more brilliant and necessary in Eastern lands than in our own) by night. It is a day of the Lord in which the light is not clear nor dark—not day nor night (Zechariah 14:6–7).

There will be periods in which the lights that guide people will give off uncertain glimmers; upon the earth there will be distress of nations, men’s hearts failing them for fear, and for looking after those things which are coming on the earth, for the powers of heaven shall be shaken (Luke 21:25–26). Such times of darkness and sorrow must be. It is through seasons such as these, when the lights of human wisdom and of spiritual guidance seem equally obscured, that the Church must go forward.

The chaos precedes creation, and it is through chaos again that the Church of Christ must pass to the new heaven and new earth. These trumpet-visions, if read alongside the story of Genesis, seem like the undoing of creation: the vegetation is struck, the earth and sea are intermingled, the lights of the heavens are darkened, and the living things in seas and streams are destroyed; but

“Fresher life the world will draw
From their decay.”

The pulling down must precede the building up; the removal of the degenerate is one step towards the regeneration.