Hello Pierre, thanks for taking the time to respond.

You said:

"An interesting reprise of Bill Farmer's argument for Matthew's priority. However, the existence of the "Q" materials shared by Matthew and Luke but not Mark is a serious lacuna in your article."

That's just it -- Q doesn't exist.

There has never been a Q document found, nor any reference to a Q document in any of the church fathers.

All the evidence we do have from history declares Matthew to be the first Gospel written. If this is true, then it removes any reason to think that something like Q might exist.

Q only exists in the hypothetical scenario that Mark wrote first. It was only needed to explain the origin of the shared material in Matthew and Luke that doesn't appear in Mark.

But if Matthew wrote first, then there's no reason for Q. Luke simply used the material in Matthew. Case closed, no reason for Q.

You said:

"Not to mention that Matthew and Luke each has special materials of their own."

Of course they do.

Every Gospel has unique material.

By itself, that doesn't tell you anything about who wrote first. It only means each Gospel writer had unique material they felt worthy of inclusion.

You said:

"Finally John is the outlier but may well be earlier than the other three."

There is no hint historically that John was first.

Every mention from history indicates that John wrote last, after Matthew, Mark, and Luke were well known.