I remember hearing an interview with Dave Brubeck on NPR, in which he mentioned that the melody of Schutz's "Oh, Sacred Head" (also found in Bach's St. Matthew'

I remember hearing an interview with Dave Brubeck on NPR, in which he mentioned that the melody of Schutz's "Oh, Sacred Head" (also found in Bach's St. Matthew's Passion) was from a folk melody, a song about a guy being jilted.