Chassidism is a Jewish sect that developed during the 18th and 19th centuries in Poland and the Ukraine. As in any other religious and/or God-affirming traditions, music plays an important part in the spiritual life either by its presence or its absence. The former is the case with the Chassidic Jews. Stylistically, the theoretical structures and conceptual framework for music are found in the Zohar, the book of splendor, which holds a prominent place in the tradition. Zohar was written between the second and 13th centuries as a commentary on the Pentateuch. Ideas expressed in the music of the Chassidic Jews include, but are not limited to, angelic harmonies, secret melodies, a disregard for art music, devotion to God, direct communication and access to God, and inspired melodies and rhythms as music is spontaneously sung while participants revel in a state of ecstasy. Characteristically, the musical expressions fill the spectrum of melodic and rhythmic ambiance from the meditative to the explosive.