Your explanation is extremely complicated and logistically implausible.rgprice wrote: ↑Sun Apr 18, 2021 4:54 am Just to throw out one more example. Luke 11:29-32 was not present in Marcion. This section, about the "sign of Jonah", looks very much like something that had to have been copied by Luke from Matthew. The whole thing is almost identical between the two in ways that its extremely difficult to imagine would have happened by two people independently working from sources. The 2DH ends up mostly relying on a claim that this is a Mark-Q overlap, therefore explaining that the section existed in Q almost identical to how it exists in Luke and Matthew, and Mark had derived his content from Q but made alternations to it.
However, all of this is much more simply explained by the scenario that Mark 8:12-9:1 was originally developed by Mark. Marcion's Gospel is derived from Mark and mostly follows it in this section. Proto-Luke was the same as Marcion's Gospel here. Matthew, working from proto-Luke, added the part about Jonah. Luke harmonized proto-Luke with Matthew, adding the part about Jonah to his Gospel as well.
When Matthew worked from proto-Luke, he did stuff like collect up the teachings that went into the Sermon on the Mount. Thus, Matthew's Sermon on the Mount is a more developed version of the Sermon on the Plain, with the various teachings found in proto-Luke collected together. In this content, Luke is more primitive and Matthew more developed. Thus, Luke has priority in regard to those passages. In the passage about Jonah, however, Matthew has priority over Luke.
What amazes me is that the whole case for Q is about trying to resolve the observation of "alternating priority", where sometimes it appears that Luke copied from Matthew and sometimes that Matthew copied from Luke. That's what so many scholars see. But instead of simply accepting that that is exactly what happened, they embrace "Q", with some proposal about how both works were independently created in in a single step from mutual sources.
The easy explanation is that its exactly what it looks like. B copied from A, then A was harmonized with B creating A'.
It should be most obvious that the story of Jonah does not require either the authors of gLuke or Matthew to copy one another since the Jonah story is found in another known source the book of Jonah in the OT written hundreds of years before the Gospels.