stages. Parsifal Wagner's final opera, Parsifal (1882), which was his only work written especially for his Bayreuth Festspielhaus and which is described in the score as a "Bühnenweihfestspiel" ("festival play for the consecration of the stage"), has a storyline suggested by elements of the legend of the Holy Grail. It also carries elements of Buddhist renunciation suggested by Wagner's readings of Schopenhauer. Wagner described it to Cosima as his "last card". It remains controversial because of its treatment of Christianity, its eroticism, and its expression, as perceived by some commentators, of German nationalism and antisemitism. Despite the composer's own description of the opera to King Ludwig as "this most Christian of works", Ulrike Kienzle has commented that "Wagner's turn to Christian mythology, upon which the imagery and spiritual contents of Parsifal rest, is idiosyncratic and contradicts Christian dogma in many ways." Musically the opera has been held to represent a continuing development of the composer's style, and Millington describes it as "a diaphanous score of unearthly beauty and refinement". Non-operatic music Apart from his operas, Wagner composed relatively few pieces of music. These include a symphony in C major (written at the age of 19), the Faust Overture (the only completed part of an intended symphony on the subject), some concert overtures, and choral and piano pieces. His most commonly performed work that is not an extract from an opera is the Siegfried Idyll for chamber orchestra, which has several motifs in common with the Ring cycle. The Wesendonck Lieder are also often performed, either in the original piano version, or with orchestral accompaniment. More rarely performed are the American Centennial March (1876), and Das Liebesmahl der Apostel (The Love Feast of the Apostles), a piece for male choruses and orchestra composed in 1843 for the city of Dresden. After completing Parsifal, Wagner expressed his intention to turn to the writing of symphonies, and several sketches dating from the late 1870s and early 1880s have been identified as work towards this end. The overtures and certain orchestral passages from Wagner's middle and late-stage operas are commonly played as concert pieces. For most of these, Wagner wrote or rewrote short passages to ensure musical coherence. The "Bridal Chorus" from Lohengrin is frequently played as the bride's processional wedding march in English-speaking countries. Prose writings Wagner was an extremely prolific writer, authoring many books, poems, and articles, as well as voluminous correspondence.