The kings of the earth did not believe, nor any people of the world, that an enemy or a foe could enter the gates of Jerusalem.
He confirms the same thing; for when a thing incredible happens, either we are extremely stupid, or we must be moved and affected. The Prophet, then, now says that the destruction of the city of Jerusalem had been incredible, because God had defended it by his power; it was also so fortified that no one believed that it could be taken, and the grandeur of the city was known everywhere.
Jerusalem, once splendid as fine gold, has become dull and worthless dross. The temple's gold was sullied in the fire, its precious stones scattered like rubbish through the streets. When God withdrew His presence through provoked judgment, no wonder the sanctuary itself was profaned and cast down.
AI summary
Commenting on Lamentations 4:1-12
The kings of the earth, and all the inhabitants of the world,.... Not only the neighbouring nations, and the kings of them, but even such in all parts of the world that knew anything of Jerusalem: would not have believed that the adversary and the enemy would have entered into the gates of Jerusalem; when it was besieging, they did not believe it would be...