John Calvin's Bible Commentary
Jeremiah 47:6
Here Jeremiah turns to address the sword of God; and it is a happy apostrophe. It is very striking and forcible, when the Prophet at one time addresses the land of the Philistines, and at another, the sword of God; and he had no other object but to confirm his prophecy, of which otherwise, the Jews might have doubted.
He then says, Ho! sword of Jehovah! Though he puts here the preposition ל, lamed, which designates the dative case; yet it is often redundant. There is, in the meantime, no doubt but that he intimates that the slaughter of which he speaks would be, as it were, by God’s sword, or by a sword hired by him. Thus he shews that the Chaldeans would do the work of God in destroying the land of the Philistines.
How long, he says, ere thou restest! Hide thyself in thy sheath, rest and be still Here the Prophet assumes the character of another, as though he wished to soothe with blandishments the sword of God, and mitigate its fury. “O sword,” he says, “spare them, leave off to rage against the Philistines.” The Prophet, it is certain, had no such feeling; but, as we have said elsewhere, it was a common thing with the Prophets to assume different characters while endeavor-ing more fully to confirm their doctrine. It is the same, then, as though he represented here the Philistines; and the Prophets speak also often in the person of those on whom they denounce the vengeance of God. It is here as though he had said, “The Philistines will humbly ask pardon of God’s sword, but it will be without advantage or profit; for when they seek to mitigate the wrath of God, the answer will be, How can it rest?” Here the Prophet, as it were, reproves himself, “I act foolishly in wishing to repress the sword of God; for how canst thou rest?” It could not be; and why? because God hath commanded it against Ashkelon He now changes the person, but without any injury to the sense. God, then, hath commanded it, therefore the whole world would intercede in vain; in vain also will the Philistines deprecate it; for it will not be in their power to mitigate God’s wrath, when it shall burn against them and against Ashkelon.