Oral gospel traditions called the M source for Matthew and the L source for Luke, which may have been a mix of written and oral material (see Two-source hypothesis). Most scholars believe that the author of John's gospel used oral and written sources different from those available to the Synoptic authors – a "signs" source, a "revelatory discourse" source, and others – although there are indications that a later editor of this gospel may have used Mark and Luke. Oral transmission may also be seen as a different approach to understanding the Synoptic Gospels in New Testament scholarship. Current theories attempt to link
New Testament the Gospel of Matthew, though most assert Jewish-Christian authorship. Authorship is an area of longstanding and current research and debate, with different works posing different problems for identification. While the various works have traditional ascriptions of authorship, these ascriptions are in some cases defended by scholars, and in other cases disputed or rejected. According to many (if not most) critical scholars, none of the authors of the Gospels were eyewitnesses or even explicitly claimed to be eyewitnesses. Bart Ehrman of the University of North Carolina has argued for a scholarly consensus that many New Testament books were not written by