John Calvin Commentary Isaiah 34:4

"And all the host of heaven shall be dissolved, and the heavens shall be rolled together as a scroll; and all their host shall fade away, as the leaf fadeth from off the vine, and as a fading [leaf] from the fig-tree." — Isaiah 34:4 (ASV)

And all the armies of heaven shall fade away. Isaiah employs an exaggerated style, as other prophets are accustomed to do, to represent vividly the dreadful nature of God’s judgment and to make an impression on people’s hearts that were dull and sluggish. Otherwise, his discourse would have lacked energy and would have had little influence on careless people.

He therefore adds that the stars themselves, amidst such slaughter, will gather blackness as if they were ready to faint, and he does so to show more fully that it will be a mournful calamity. Similarly, just as in a dark and troubled sky the clouds appear to be folded together, the sun and stars to grow pale and, so to speak, to faint, and all those heavenly bodies to totter and show signs of ruin, he declares that it will happen this way at that time, and that everything will be full of the saddest lamentation.

These statements must be understood to relate to people’s perception, for heaven is not moved from its place. But when the Lord gives displays of his anger, we are terrified as if the Lord were folding up or throwing down the heavens. This is not because anything of this kind actually happens in heaven; rather, he speaks to careless people, who needed to be addressed in this way, so that they would not imagine the subject to be trivial or a fitting subject for scorn. You will be seized with such terror that you will think the sky is falling on your heads. It is the just punishment of indifference that wicked people, who are not moved by any fear of God, dread their own shadow and tremble at the rustling of a falling leaf (Leviticus 26:36), as much as if the sun were falling from heaven. Yet it also denotes a dreadful revolution of affairs, by which everything will be subverted and disturbed.