The scholarly effort to reconstruct an "authentic" historical picture of Jesus was a product of the Enlightenment skepticism of the late eighteenth century. Bible scholar Gerd Theissen explains that "It was concerned with presenting a historically true life of Jesus that functioned theologically as a critical force over against Roman Catholic Christology." The first scholar to separate the historical Jesus from the theological Jesus in this way was philosopher, writer, classicist, Hebraist and Enlightenment free thinker Hermann Samuel Reimarus (1694–1768). Copies of Reimarus' writings were discovered by G. E. Lessing (1729–1781) in the library at Wolfenbüttel where Lessing was the librarian. Reimarus had left permission for his work to be published after his death, and Lessing did so between 1774 and 1778, publishing them as "Die Fragmente eines unbekannten Autors" ("The Fragments of an Unknown Author"). Over time, they came to be known as the "Wolfenbüttel Fragments" after the library where Lessing worked. Reimarus distinguished between what Jesus taught and how he is portrayed in the New Testament. According to Reimarus, Jesus was a political Messiah who failed at creating political change and was executed. His disciples then stole the body and invented the story of the resurrection for personal gain. Reimarus' controversial work prompted a response from "the father of historical critical research" Johann Semler in 1779, "Beantwortung der Fragmente eines Ungenannten" ("Answering the Fragments of an Unknown"). Semler refuted Reimarus' arguments, but it was of little consequence. Reimarus' writings had already made lasting changes by making it clear criticism could exist independently of theology and faith, and by founding historical Jesus studies within that non-sectarian view.