Adam Clarke on Psalms 137:6

Let my tongue cleave - Let me lose my voice, and all its powers of melody; my tongue, and all its faculty of speech; my ear, and its discernment of sounds; if I do not prefer my country, my people, and the ordinances of my God, beyond all these, and whatever may constitute the chiefest joy I can possess in aught else beside. This is truly patriotic, truly noble and dignified. Such sentiments can only be found in the hearts and mouths of those slaves whom the grace of God has made free.