responsible for the music at four churches. He provided church music for the two main churches, St. Thomas and St. Nicholas, and occasionally also for two others, the New Church and St. Peter. Bach took office in the middle of the liturgical year, on the first Sunday after Trinity. In Leipzig, cantata music was expected on Sundays and on feast days, except during the tempus clausum ("silent periods") of Advent and Lent. Lutheran Leipzig observed several Marian feasts, including Annunciation on 25 March, nine months before Christmas. In 1725, the feast fell on Palm Sunday. Annunciation was the only occasion for festive music during Lent. The prescribed readings were, as the epistle, Isaiah's prophecy of the birth of the Messiah (Isaiah 7:10–16), and from the Gospel of Luke, the angel Gabriel announcing the birth of Jesus (Luke 1:26–38). Cantata cycles In his first twelve months in office, Bach decided to compose new works for almost all liturgical occasions. These works became known as his first cantata cycle. In his second year in office, Bach composed a cycle of chorale cantatas, with each cantata based on one Lutheran hymn, for the liturgical occasions. The choice of hymn for each of the cantatas was probably made according to the wishes of a local minister, who based the choices upon the prescribed readings and his plans for sermons. Compared to the first cycle, the music has less emphasis on biblical texts, but more on the use of chorale text and melody. Bach's earliest extant chorale cantata, , written more than a decade before arriving in Leipzig, followed the principle, that is, it adopted the text of all stanzas of the hymn without modification, the hymn's melody being used throughout. Most of the chorale cantatas Bach wrote in his second year in Leipzig, including , were formatted differently. In this structure, the outer stanzas of the hymn, and its melody, were retained in the outer movements of the cantata: typically the first stanza was set as an opening chorale fantasia, and the last as a closing four-part chorale. The inner stanzas of the hymn were rephrased into recitatives and arias for the cantata's inner movements, their setting mostly not based on the hymn tune. Hymn Bach's cantata is based on Philipp Nicolai's hymn with the same name. Nicolai wrote the hymn when he was pastor in Unna and faced an outbreak of the plague,