Blessed shall he be who takes your little ones and dashes them against the rock!
Babylon means the kingdom, not the city. The Jews gathered by the rivers where they could worship in the open air, since they had no synagogues there. This is history written as it happened, not prophecy: the captivity has come, and the Psalmist speaks for the whole Church under this affliction.
AI summary
Commenting on Psalm 137:1-9
Happy shall he be, that taketh and dasheth thy little ones against the stones. Fierce was the heart of the Jew who had seen his beloved city the scene of such terrific butchery. His heart pronounced like sentence upon Babylon. She should be scourged with her own whip of wire.
The pious Jews in Babylon, having afflicted themselves with the thoughts of the ruins of Jerusalem, here please themselves with the prospect of the ruin of her impenitent implacable enemies; but this not from a spirit of revenge, but from a holy zeal for the glory of God and the honour of his kingdom. I.
Commenting on Psalm 137:7-9