In 1 Timothy 5:18 it says:
For the Scripture says, “You shall not muzzle an ox when it treads out the grain,” and,“The laborer deserves his wages.”
One text quoted is from the Jewish Scriptures. The other is a saying attributed to Jesus in the Gospels.
And so the author of this text, not only do one or more written Gospels exist, but they are being viewed as Scripture.
There could perhaps be other explanations of what we find here – that a saying of Jesus was misremembered as being from the Hebrew Bible. But if it is deemed more likely that the author intends to refer to Gospels as part of the Scriptures, then given the absence of reference to written Gospels in the authentic letters of Paul, positing that Paul actually wrote 1 Timothy seems particularly difficult.
There are certainly ways of avoiding this conclusion, but it isn’t clear to me that any of them seem to provide a more probable reading of the evidence than what I’ve outline above.
What do others think?