Gospel of Thomas in the late 2nd century that "since there are four quarters of the earth ... it is fitting that the church should have four pillars ... the four Gospels" ("Against Heresies", 3.11.8), and then shortly thereafter made the first known quotation from a fourth gospel—the canonical version of the Gospel of John. The late 2nd-century Muratorian fragment also recognizes only the three synoptic gospels and John. Bible scholar Bruce Metzger wrote regarding the formation of the New Testament canon, "Although the fringes of the emerging canon remained unsettled for generations, a high degree of unanimity concerning the greater part of
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