There are very few pieces of music which make me want to wax poetic. This is probably my favorite piece of classical music. And while most people can probably recognize the opening — it’s associate with a lot of horror movies — they don’t always recognize the rest of it. For a piece that seems foreboding at the beginning, it resolves into one of the most beautiful and uplifting songs. The mathematical purity of the song is one of its strengths. And it is progress and light and forward movement and call and answer, and a hundred other things that match the soaring cathedral halls that are meant to contain it. As an organ piece it simply swells to fill the space around it echoing and building on itself. It is sublime.