Words are the pen of the heart, but music is the pen of the soul.
Shneur Zalman
Shneur Zalman of Liadi, commonly known as the Alter Rebbe or Baal Hatanya, was a rabbi and the founder and first Rebbe of Chabad, a branch of Hasidic Judaism. He wrote many works and is best known for Shulchan Aruch HaRav, Tanya, and his Siddur Torah Ohr, compiled according to the Nusach Ari.