The present volume offers the first scholarly discussion of Günter Lüling's (1928-2014) work. Lüling's views, long passages of the Qur'ān are originally mere reworking of pre-Islamic Christian hymns have not received the scholarly attention they deserve, since they were published at the beginning of the 70s of the previous century. Lüling attempted to reconstruct an "Ur-Qur'ān" in order to show that Islam emerged in a Christian context in Mecca. He also believed that Muhammad converted from Trinitarian Christianity to paganism and that the Kaaba was a church. Lüling's hermeneutical approach to the Qur'ān and other Arabic sources on early Islam is, for the first time, the subject of the studies included in the present book. In addition, the volume offers interesting insights in the law case which accompanied the publication of Lüling's work.