John Calvin Commentary Jeremiah 4:29

"Every city fleeth for the noise of the horsemen and bowmen; they go into the thickets, and climb up upon the rocks: every city is forsaken, and not a man dwelleth therein." — Jeremiah 4:29 (ASV)

By saying that at the voice or sound of horsemen and bowmen there would be a universal flight, he means that the enemies would come with such impetuosity that the Jews would not dare to wait for their presence but would flee here and there before they were attacked. For the word voice or sound, no doubt, is set here in opposition to wounds.

They swelled, we know, with amazing pride; hence the Prophet ridicules that false confidence by which they were so inebriated as not to dread God’s judgment. “The sound alone of enemies,” he says, “will frighten you, so that all the cities, being left by their inhabitants, will easily fall into their hands, for walls will not defend themselves; indeed, the gates will be open.” Flee then will every city; that is, all the cities will have recourse to flight.

Then it follows, Ascend will they into the clouds, or into thicknesses: this may be applied to the enemies, to show that they would be so nimble and active as to fly, as it were, to the clouds, and climb the highest rocks. But I prefer to connect this sentence with the former, as intimating that to ascend the clouds would not be too arduous for the Jews in their anxious flight.

Since the tops of mountains were often covered with thick trees, forming a dark shade, this passage may mean that they fled to such places. However this may have been, the Prophet here, no doubt, refers to such high situations. Hence, the meaning would be more evident if we retain the word 'clouds'.

As to what is intended, we see that this is clear; namely, that the enemies of the Jews would in swiftness be equal to eagles while pursuing them. Or, what is more commonly thought, the terror felt by the Jews would be so great that in their flight they would not seek recesses near at hand, but would flee to the highest tops of mountains and hide themselves there among the trees, as though they had climbed into the clouds.

They would ascend into craggy rocks, as they could not otherwise consider themselves safe from the attacks of their enemies.

He then adds that every city would be forsaken, so that no one would dwell in them. We see that the Prophet always had this in view—to rouse the Jews, who had deaf ears and stony hearts, so that they felt no concern for their own calamities and even boldly despised God, as though they had made a covenant with death, according to what is said in another place (Isaiah 28:15). He adds further—