for there our captors requested a song; our tormentors demanded songs of joy: “Sing us a song of Zion.”
PSALM 137 At the Babylonish captivity the established order of God’s worship was overthrown, and the Psalmist complains, in the name of the Church at large, of the taunts which the enemy east upon the name of God, addressing at the same time a word of comfort to his people under their captivity, to cheer them with the hope of deliverance. Psalm 137:1-4 1.
Commenting on Psalm 137:1-9
For there they that carried us away captive required of us a song. It was ill to be a singer at all when it was demanded that this talent should go into bondage to an oppressor's will. Better be dumb than be forced to please an enemy with forced song. What cruelty to make a people sigh, and then require them to sing!
St. John Chrysostom observes the improvement such tribulation effected in the Jews, who previously derided, nay, even put to death, some of the prophets; but now that they were captives in a foreign land, they would not attempt to expose their sacred hymns to the ridicule of the Gentiles.— Robert Bellarmine.
Commenting on Psalm 137:3