that contained polyphony (more than one musical part playing at a time), fearing that it would cause people to doubt the unity of God. The church also banned the musical interval of an augmented fourth, the distance between C and F-sharp and also known as a tritone (the interval in Leonard Bernstein’s West Side Story when Tony sings the name “Maria”). This interval was considered so dissonant that it must have been the work of Lucifer, and so the church named it Diabolus in musica.
