Paul Simon wrote American Tune based on a melody by Johann Sebastian Bach, adapted it slightly and gave it bittersweet lyrics. It showed up in 1973 on his album There Goes Rhymin’ Simon and was probably the best song on that album, and one of the best of his career.
On this Memorial Day 2011, have a listen to his performance with Art Garfunkel at The Concert in Central Park. The two of them reunited for this free event in 1981. Garfunkel solos at first, and when Simon comes in it’s their legendary harmony all over again.
Then, listen to a hymn based on the same melody: O Sacred Head Now Wounded. Bach himself had adapted the tune from a love ballad by Hans Leo Hassler. Really worth a listen.