Did a “Gospel of Matthias” ever exist?
I’m skeptical, but some early Christian authors thought so, & Clement of Alexandria included a handful of teachings that he attributed to Matthias in his Stromateis. Here’s my entry on it for the e-Clavis: Christian Apocrypha. #apocrypha
https://www.nasscal.com/e-clavis-christian-apocrypha/gospel-of-matthias/