John Calvin Commentary Jeremiah 50:28

"The voice of them that flee and escape out of the land of Babylon, to declare in Zion the vengeance of Jehovah our God, the vengeance of his temple." — Jeremiah 50:28 (ASV)

The Prophet again shows that God, in punishing Babylon, would give a sure proof of His favor toward His church. For this prophecy would have been uninteresting to the faithful if they did not know that God would be an enemy to that great monarchy because He had undertaken the care of their safety. Therefore, the Prophet often calls the attention of the faithful to this fact: that God’s vengeance on the Babylonians would be a sure proof to them of God’s favor, by which He had once embraced them and which He would continue to show them to the end.

This, then, was the Prophet's design when he said, The voice of fleers and of those who escape from the land of Babylon, etc., as if he had said, “Babylon is on many accounts worthy of destruction, but God, in destroying it, will have regard for His own people and will effectively show that He is the Father of the people whom He has adopted.” Jeremiah afterward exhorts the faithful to show their gratitude.

There are, then, two things here:

1. That when God destroyed Babylon, the people would therefore perceive with certainty how dear they were to God.
2. From this truth flows an exhortation that the faithful were not to be silent about such a singular benefit from God, but were to proclaim their deliverance.

Therefore he says, The voice of fleers and of those who escape from the land of Babylon, to announce in Sion, etc. By saying in Sion, he shows for what purpose God intended to gather His people: namely, that He might again be worshipped as formerly—in His own Temple.

He adds, to announce in Sion the vengeance of our God. The vengeance of God is to be understood here in an active sense, signifying the vengeance which God would execute. The vengeance of the Temple, which immediately follows, is to be understood passively, as meaning the vengeance by which God would avenge the indignity offered to the Temple. God then takes vengeance, and God’s Temple is defended from contempt and reproach.

We now see, then, the meaning of this passage. The Prophet teaches us three things:

1. God would have regard for His people in so rigidly punishing Babylon.
2. He adds an exhortation, so that the faithful would not be unthankful to God, but would instead acknowledge that God, for the sake of their deliverance, had undertaken war against that monarchy.
3. He shows the purpose: that the people who had been scattered (as it is said in Psalm 147:2, God is He who gathers the dispersed of Israel) might again be gathered together.

Therefore, since the Jews were like a mutilated body among the Chaldeans, the Prophet shows that that monarchy would be scattered so that the faithful might again be gathered, and that all might worship God together in the Temple, or on Mount Sion.