Martin Luther thought that the congregation (people worshipping in church) should have music to sing that was not too difficult. He thought that the words should be in German instead of Latin so that everybody would understand what they were singing about. Luther wrote the words of many chorales himself. He even composed some of melodies himself, such as "Ein' feste Burg" ("A Mighty Fortress"). Sometimes he used the traditional Gregorian Chant melodies from the Catholic worship and added new German words to it, for example "Christ lag in Todesbanden" ("Christ lay in Death's Dark Bonds").