In 1939 Schoenberg was facing the challenge to complete his Second Chamber Symphony, which was started 33 years earlier. Through a harmonic study of his sketches, I propose that Schoenberg made an implicit application of Jewish cyclical repetitions as a creative concept to overcome the long compositional block. This article is divided into two parts. I begin with a discussion on the use of cyclical form in the modern history of Western classical music before laying out some of Schoenberg’s ideas on repetition. Thereafter, harmonic analyses of the two complete movements of the Second Chamber Symphony as well as fragments from the third movement are used to support the argument that an extended cyclic form could have been adopted by Schoenberg as a method of musical organization during the first few years after his conversion back to Judaism. The cyclical formation of Schoenberg’s Second Chamber Symphony could critically be part of an unconscious and anxious process that reveals itself as part of the Semitic musical genealogy from Mendelssohn to Mahler.