Babylon was so rich and potent a nation, and had been so great a conqueror, that people looking only with the eye of sense, and judging according to probabilities in the eyes of men, might well ask how these things could possibly be. To which the prophet here answereth, that the hand of God was to be eyed in the case, this was the Lord's work upon the Chaldeans; God had opened his armoury, and the Medes were to make use of the weapons of his indignation. He who threatened this destruction was able to carry it through, and it was no great matter what weapons either the Babylonians had to defend themselves, or the Medes to offend them, God's power and strength as only to be regarded.
Related Commentaries of Jeremiah 50:25
Jeremiah 50:25
25 The LORD hath opened his armoury, and hath brought forth the weapons of his indignation: for this is the work of the Lord GOD of hosts in the land of the Chaldeans.