The PGH mentions the city of Gerasa which was an ancient city in
Palestine which was destroyed by the 10th Roman legion Firensis in AD 70.
Only the very oldest existing manuscripts of the canonical gospels mention
the city of Gerasa while later manuscripts refer to the area as the land of
the Gerasenes. Thus the author of the original source of the PGH may have
lived prior to AD 70.

The sequence of the PGH also parallels many aspects of the theoretical
"Q" text. The Greek texts of Matthew and Luke in some areas are letter for
letter matches which have led some scholars to theorize that at one time a
single text "Q" was formed from an early form of Matthew and of Luke and then
later portions of our modern forms of Matthew and Luke were copied from this
single gospel text. Additionally, in the modern text of Luke the "Parable of
the Lamp" occurs in both Chapter 8 and Chapter 11. It has been theorized that
an early text that contained Luke had only one "Parable of the Lamp" and that
the parable was either cut in half or duplicated in our modern texts. The PGH
sequence combines portions of Luke Ch. 8 and 11 and only has a single account
of the "Parable of the Lamp" just as some scholars have theorized would've
existed in the single gospel forerunner of the modern text of Luke.

Scholars have also theorized that the "Q" text would've been
constructed into categories and composed of lists such as a list of parables.
This idea was formulated in part based on the gospel of Thomas found at Nag
Hammadi. The PGH does form the gospel account into categories or groupings
and there are two major groupings of parables in its sequence just as
theorized for the "Q" text.

The event sequence of the PGH also enhances the account of the four
gospels. The sequence produces cause and effect relationships between events