John Calvin on Jeremiah 50:14

The Prophet now turns to address the Medes and Persians, and instigates them, in the name of God, to destroy Babylon. We have already said, why the Prophets assume authority over all nations, even that they might show that God’s power is connected with his word. For men do not easily apprehend the efficacy of God’s word, and think that the air is to no purpose beaten by an empty sound. Hence the Prophets show that God has his hand extended whenever he speaks, so that nothing is announced in vain. This then is the reason why the Prophet now, as before, commands the Persians and Medes strenuously to exert themselves in attacking Babylon.

He says, first, Set in order, that is, the battle, or the assault; set in order against Babylon; and then, around, so that no escape might be open to them. He adds, All ye who bend the bow, for this mode of fighting was common among the Medes and Persians, as it appeared elsewhere; and the Orientals still follow the same practice, for they throw darts at their enemy, and move here and there, for they do not engage in pitched battles. he afterwards says, Throw or shoot at her, spare not the arrow; the singular is here used for the plural, he adds the reason, because they have acted wickedly against God. Or literally, “Because against Jehovah has she sinned.” — Ed.

Though the iniquity of Babylon was manifold, there is yet no doubt but that God here undertakes the cause of his Church. Then, of all the sins of the Chaldeans, the chief was this, that they had oppressed the Church of God; for we know with what favor God regards his children, so that he who hurts them toucheth the apple of his eye, as he testifies elsewhere. (Zechariah 2:8.) This singular effect of love Jeremiah sets forth when he says, that the Chaldeans had acted wickedly against Jehovah, even because they had tyrannically oppressed his Church.

Now God will have nothing, as it were, apart from his children: and hence we learn a useful doctrine, — that the salvation of his Church is so precious in the sight of God, flint he regards the wrong done to the faithful as done to himself. Thus there is no reason why we should torment ourselves, when the ungodly harass us, because God will at length really show that our salvation is not less dear to him than their own eyes are to men. It afterwards follows, —

Jeremiah 50:15

15. Shout against her round about: she hath given her hand: her foundations are fallen, her walls are thrown down: for it is the vengeance of the LORD: take vengeance upon her; as she hath done, do unto her.

15. Vociferamini contra eam per circuitum; dedit manum suam; ceciderunt fundamenta ejus, diruti sunt muri ejus, quia ultio Jehovae haec; ultionem sumite de ea; quemadmodum fecit, facite ei.