The Gospel and the Gospels

A robust scholarly defense of the distinctiveness of the canonical Gospels.   Do the four New Testament gospels share some essence that distinguishes them from noncanonical early Gospels? The tendency among biblical scholars of late has been to declare the answer to this question  no —that Matthew, Mark, Luke, and John were grouped together by happenstance and are defended as canonical today despite there being no essential commonalities between them.  Simon Gathercole challe