There are just way too many variables. Even if all four points above were true (and Hegesippus' direct connection to Syria can by no means be assumed), there can be many varied responses to different phrases. The contradiction between "eyes have not seen, ears not heard" and "blessed are your eyes and ears" is exegetical; it need not have anything to do with Jewish or gentile parties or classes. If we are taking the most direct route with the evidence for Hegesippus, then do you not suspect he is reacting to the lines in 1 Clement, not necessarily in 1 Corinthians itself?John2 wrote:Sure, all Jewish Christians weren't exactly the same (if I recall correctly, some were even said to be more in line with the NT), but setting aside its disputed ending, the Didache has a lot in common with Hegesippus. They are both Jewish Christian, non-Pauline, use one Matthew-type gospel and possibly come from Syria/Palestine. And since Hegesippus was hostile to the "no eye has seen" expression and thought it was based on Matthew, is it a stretch to think that it wouldn't be in the Didache?
I see no way of demonstrating that Hegesippus knew or respected the Didache, nor that the particular "gospel of the Hebrews" or "Syriac gospel" that he apparently quoted from is connected to the Didache.