Michael Goulder proposed the idea that, after the death of Jesus, early Christianity formed in the synagogue and Mark’s gospel was written from these stories of Jesus that corresponded to Jewish Sabbaths and holy days of the Jewish year. This concept is discussed at length in John Spong’s “Biblical Literalism: A Gentile Heresy”. Examples are: the transfiguration is noted in exactly the location where the observance of Dedication-Hanukkah occurs in the Jewish liturgical year; Jesus and harvest occurs at Sukkoth, etc. 

Spong and/or Goulder felt that Mark provided Jesus stories for only 6 1/2 months of the year. Therefore, Matthew and Luke gospels included more of genealogy, birth, early years, and so on to fill out all 12 months of the liturgical year.

Any thoughts as to the likelihood that this approach is accurate?