1942. In the Chapel of Indulgences () there is a chamber organ originally from East Prussia. It has been in the chapel since 1948. It has a single manual and eight voices, with separate control of bass and descant parts. It was built by Johannes Schwarz in 1723 and from 1724 was the organ of the (Castle Chapel) of Dönhofstädt near Rastenburg (now Kętrzyn, Poland). From there it was acquired by Lübeck organ builder Karl Kemper in 1933. For a few years it was in the choir of St. Catherine's Church, Lübeck. Then, Walter Kraft brought it, as a temporary measure, to the Chapel of Indulgences at St. Mary's, this being the first part of the church to be ready for church services after the War. Today this organ provides the accompaniment for prayers as well as the Sunday services that are held in the Chapel of Indulgences from January to March. Organists Two 17th-century organists, especially, shaped the development of the musical tradition of St. Mary's: Franz Tunder from 1642 until his death in 1667, and his successor and son-in-law, Dieterich Buxtehude, from 1668 to 1707. Both were defining representatives of the north German organ school and were prominent both as organists and as composers. In 1705 Johann Sebastian Bach came to Lübeck to observe and learn from Buxtehude, and Georg Friedrich Händel and Johann Mattheson had already been guests of Buxtehude in 1703. Since then, the position of organist at St. Mary's Church has been one of the most prestigious in Germany. With their evening concerts, Tunder and Buxtehude were the first to introduce church concerts independent of religious services. Buxtehude developed a fixed format, with a series of five concerts on the two last Sundays of the Trinity period (i.e. the last two Sundays before Advent) and the second, third, and fourth Sunday in Advent. This very successful series of concerts was continued by Buxtehude's successors, Johann Christian Schieferdecker (1679–1732), (1696–1757), his son (1720–1781) and Johann Wilhelm Cornelius von Königslöw. For the evening concerts they each composed a series of Biblical oratorios, including [Israel's Idol Worship in the Desert] (1758), Absalon (1761) and Goliath (1762) by Adolf Kunzen and '' [The Finding of Baby Moses] and [The Saviour of the World is born] (1788), [Death, Resurrection and Judgment] (1790), and [David's Lament on Mount Hermon (Psalm 42)] (1793) by Königslöw. Around 1810 this tradition ended for a