John Calvin Commentary Jeremiah 48:10

"Cursed be he that doeth the work of Jehovah negligently; and cursed be he that keepeth back his sword from blood." — Jeremiah 48:10 (ASV)

The Prophet here encourages the Chaldeans to severity, so that they would not stop until they had destroyed that nation. We have said that the prophets assumed different characters, so that what they said might be more impressive. The Chaldeans were not indeed the disciples of Jeremiah; nor was this exhortation intended for them, but rather so that the Israelites might know that what they heard from the mouth of Jeremiah was certain. He then turns to address the Chaldeans. Just as he previously proclaimed to anyone who might be present, Give wings to Moab; so now another apostrophe follows: Cursed, etc. — to whom does he speak? To the Chaldeans. And yet, the Prophet did not address them as though he could accomplish anything; but, as I have said, his focus was on the Jews.

This passage has been very absurdly explained, and it is commonly quoted as though the Prophet had said that we ought to take special care not to omit anything God commands. But in this way, they misrepresent the meaning. Therefore, we ought to remember what I have already said: that these words are addressed to the Chaldeans, as though he had said, “Spare not, but shed blood, and let no humanity move you, for it is the work of God. God has armed you, that you might fully execute his judgment and spare no blood; you will then be accursed, unless you execute his vengeance.” This is not, indeed, a common way of speaking; but regarding the subject and meaning, there is no ambiguity. It is as if he had said, “Go on courageously and boldly execute God’s vengeance, since punishment has been declared against them.” Just as when soldiers delay idly, their leader, if present, not only exhorts them but also urges them on with rebukes and threats to arouse their eagerness, so the Prophet here shows that God, as if present with the Chaldeans, would chide their sloth: “Why do you stop? Cursed is everyone who will not shed blood and who will not destroy them, from the least to the greatest.”

But the whole significance of the passage is found in the expression that the destruction of that ungodly nation was the work of Jehovah. It is as if he had said, “Though the Chaldeans will lay waste the land of Moab, and will do this not to obey God, but from avarice and ambition, it will still be the work of God. For God has hired the Chaldeans for this purpose, so that they might destroy the Moabites, even though they may think of no such thing.”