Jeremiah 51:14

The Prophet more fully confirms what he had said by introducing God as making an oath; and it is the most solemn manner of confirmation when God swears by his own name. But he speaks of God in the language of men when he says that he swears by his own soul; for it is a kind of protestation when men swear by their own souls, as though they laid down or pledged their own life. Whoever then swears by his own soul, means that as his own life is dear to him, he thus lays it down as a pledge, that were he to deceive by perjury, God would be an avenger and take it away. This is suitable to men, not to God; but what does not properly belong to God is transferred to him; nor is this uncommon, as we have seen it in other places. And the more familiar is the manner of speaking adopted by God, the more it ought to touch men when he makes himself like them, and in a manner assumes their person as though he lived in the midst of them.

But we must still remember why the Prophet introduces God as making an oath, even that all doubtfulness might be removed, and that more credit might be given to his prophecy; for it not only proceeded from God, but was also sealed by an oath. If I shall not fill Babylon, he says, with men as with locusts

The multitude of enemies is here opposed to the multitude of the citizens, which was very large. For we have said elsewhere that Babylon surpassed all other cities, nor was it less populous than if it were all extensive country. As then it was full of so many defenders, it might have been objected and said, “Whence can come such a number of enemies as can be sufficient to put to flight the inhabitants? for were a large army to enter, it would yet be in great danger in contending with so vast a multitude.” But the Prophet compares here the Persians and the Medes to locusts; and we know that Cyrus collected from various nations a very large army, nay, many armies. Fulfilled then was what had been predicted by the Prophet, for Cyrus made up his forces not only from one people, but he brought with him almost all the Medes, and also led many troops from other barbarous nations. Hence then it happened, that what had been said by Jeremiah was proved by the event.

He also adds, that they would be victorious; for by thevintage song, or shout, he no doubt means a song or shout of triumph. But this song, הידד, eidad, was then in use among the Jews. Then as they did after vintage sing in token of joy, so also conquerors, exulting after victory over their enemies, had a triumphant song. And the Greek translators have rendered it κέλευσμα , or κελευμα , which is properly the song of sailors; when they see the harbor they exult with joy and sing, because they have been delivered from the dangers of the Sea, and also have completed their sailing, which is always perilous, and have come to the harbor where they more fully enjoy life, where they have pleasant air, wholesome water, and other advantages. But the simple meaning of the Prophet is, that when the Persians and the Medes entered Babylon, they would become immediately victorious, so that they would exult without a contest and without any toil, and sing a song of triumph. The Prophet now confirms his prophecy in another way, even by extolling the power of God, —