Possible Clues:

• See 6 Across
• Mass performance
• 'How Firm a Foundation,' for one
• Song of celebration
• We hear that chap’s song in Church
• One on the board at church: not her, we’re told
• "His Eye Is on the Sparrow," for one
• Marines' theme, e.g
• It certainly doesn't sound like her sort of song
• We hear it's not her song