John Calvin Commentary Jeremiah 51:29

"And the land trembleth and is in pain; for the purposes of Jehovah against Babylon do stand, to make the land of Babylon a desolation, without inhabitant." — Jeremiah 51:29 (ASV)

The Prophet no doubt endeavored to remove all doubts from the minds of the godly, which would have otherwise weakened confidence in his doctrine. It might have occurred to the minds of all that the whole world would sooner come to nothing than that Babylon should fall.

Even if it were so, says the Prophet, that the whole earth trembled, yet Babylon will be destroyed. Hence, he says, Tremble shall the land and be in pain, even because confirmed.

There is here a striking contrast between the moving of the earth and the stability of God’s purpose. The verb properly means to rise, but it is used in many places in the sense of confirming or establishing, and necessarily so in this passage. He then says, Tremble shall the land, even because confirmed shall be the thoughts of God respecting Babylon.

But he mentions thoughts in the plural, as if he were saying that whatever God had appointed and decreed would be unchangeable, and that the whole earth would sooner be shaken than that the truth of God should lose its effect. Then this verse contains nothing else but a confirmation of the whole prophecy. But the Prophet shows that even if all the hindrances of the world were in favor of the perpetuity of Babylon, yet what God had decreed respecting its destruction would be fixed and unchangeable.