Why was the first part of John's Gospel called the Book of Signs?

Answer 1

A:Early biblical scholars did not immediately recognise the dependency of John's Gospel on the synoptic gospels, but realised that there did seem to be a source document from which parts of John were derived. They called this hypothetical source document the Signs Gospel, because of the references in Johnto 'signs'.

Scholars now recognise that John's Gospel was loosely based on Luke's Gospel, with some material taken direct from Mark's Gospel, and thus the notion of a Signs Gospel, used by the author of John as a source, is no longer widely supported.