This study explores Sibelius's last and, perhaps, most enigmatic Symphony from historical (source-critical), Schenkerian, and transtextual perspectives. Through a detailed study of its genesis, musical architecture, and meaning, the author maintains that the Seventh, its composer, and its generative process, can best be understood as a series of verges: conceptual points of interaction between two or more forces. Verges between Sibelius's nature mysticism and the dramatic biographical circumstances of the period (1914-1924), between inspired and reasoned modes of composition, between genres (symphony and fantasy), between various form types, between tragic despair and hopeful yearning, between innovation and classicism, and between a host of other seeming oppositions, all define the Seventh Symphony and illuminate various facets of the composer's life and thought.