Psalm 137:1-4  from The Inclusive Bible:

By the rivers of Babylon,
we sat and wept, remembering Zion.
On the willows there
we hung up our harps
For there our captors taunted us to sing our songs,
our tormentors demanded songs of joy:
“Sing us one of the songs of Zion!”
But how could we sing a song of YHWH
in a foreign land?