Our fathers provoked the God of heaven unto wrath. Mainly by their long series of idolatries, with the moral abominations that those idolatries involved—the sacrifice of children by their own parents, the licentious rites belonging to the worship of Baal, and the unmentionable horrors practised by the devotees of the Dea Syra.
For centuries, with only short and rare intervals, "the chief of the priests, and the people, had transgressed very much after all the abominations of the heathen," and had even "polluted the house of the Lord which he had hallowed in Jerusalem" (2 Chronicles 36:14).
Therefore, he gave them into the hand of Nebuchadnezzar the king of Babylon. He punished, as he always does, national apostasy with national destruction. Making an idolatrous people, but a less guilty one, his sword, he cut off Judah, as he had previously cut off Israel, causing the national life to cease, and even removing the bulk of the people into a distant country.
Not by his own power or might did Nebuchadnezzar prevail. God could have delivered the Jews from him as easily as he had delivered them in former days from Jabin ( 4:2-24), and from Zerah (2 Chronicles 14:11-15), and from Sennacherib (2 Kings 19:20-36).
But he was otherwise minded; he "gave them into the hand of Nebuchadnezzar". He divided their counsels, paralysed their resistance, caused Pharaoh Hophra to desert their cause (2 Kings 24:7), and left them helpless and unprotected.
Nebuchadnczzar was his instrument to chastise his guilty people, and in pursuing his own ends merely worked out the purposes of the Almighty.