Possible Clues:

• Worker on the edge of song
• Song setting a conservative body on edge
• The air of a worker on the edge?
• Piece for Frenchman, The Marseillaise perhaps
• They object to an introit
• The song goes right for the non-heretic
• Thus might the insect be singing at the Border
• Music the man composed
• National melody
• Worker on edge for hymn ...