John Calvin's Bible Commentary
Jeremiah 49:14
The Prophet again shews that God would be the author of the calamity of which he speaks; for if things were viewed by men, no one could have thought that the Idumeans could in so short a time be destroyed. It was therefore necessary for the faithful to raise upwards their minds. And this the Prophet had in view when he said that all this would be from God.
But most forcible are his words when he says, We have heard a hearing; some say, “a report,” but improperly, as I think; for though, שמועה, shemuoe, often means a report or rumor, yet here it ought to be taken for a proclamation, which God published as it were by his own heralds. For the similitude is taken from men, proclaiming war against their enemies by a solemn rite. Then Jeremiah says, that avoice was heard sent from above, because it was God’s purpose publicly and openly to testify, that what we read here of the destruction of Edom would take place. We now then understand the meaning of the Prophet, when he says, A hearing have we heard from Jehovah
Then follows immediately a confirmation, a messenger, or an ambassador, is sent to the nations God, indeed, had no messenger or herald to proclaim war against the Idumeans, or to rouse up the Assyrians and Chaldeans; but the Prophets usually spoke thus, that men, being led to the very scene, might know that what was said was real, and would not be without its effect, as prophecies were as so many embassies. And according to this view, the prophets, as we have stated elsewhere, sometimes besieged and stormed cities, sometimes sounded the trumpet, even for this purpose, to show that their doctrine was linked with its execution, for God never spoke by them to no purpose or in vain. The Prophet at the same time reminds us that the Chaldeans and the Assyrians were in God’s hand, so that he could by a nod or a hiss rouse them to war, as it is said elsewhere,
“God will hiss for the fly of Egypt.” (Isaiah 7:18)
The Prophet then means, that the Chaldeans and the Assyrians would be ready to obey God, as though they were hired soldiers, and enlisted under his banner.
We now then see how forcible was this mode of speaking; for the faithful might hence learn, that it was in God’s power to perform whatever he proclaimed by his servant, because he could by one word rouse, draw, arm, and lead to war the Assyrians and the Chaldeans, as he also says, Be ye assembled, and come against her, and rise up to battle And he speaks of many nations, lest any one should think that the Idumeans would be able to resist, for he is not immediately conquered who is attacked by his enemies. But the Prophet meets this doubt, and says that there would be many nations, who, with their united strength, would come against the people of Edom, so that they would have no power to resist. Nearly the same words are found in Obadiah. It now follows —