The prelude and postlude today are tributes to two of the three composers. The prelude comes from the first section of “March on a Theme of Handel” by Alexandre Guilmant (1837-1911). It is based on the opening motif of “Lift Up Your Heads” from Handel’s Messiah.
The postlude is one of the Six Fugues on BACH, Op. 60, written by Robert Schumann (1810-1856) for the pedal piano (a type of piano with a pedalboard, like an organ). The theme of this fugue is derived from the surname Bach. In German musical nomenclature, B represents the note B flat while H represents B natural. Hence, the notes B-A-C-H in German spell B flat, A, C, B natural. This trick has often been used by composers paying homage to J.S. Bach.