It is problematic. I read a lot of academic Bible history and early church disputes. Until the canonization of the Bible, under order from Constantine, Christians had no uniform scriptures. Different regions would adopt different gospels. I believe they used the Psalms. Gospels other than canonical ones flourished. Also, different geographic areas had allegiances to different apostles. Their "founder" was important. St. Thomas supposedly went to India. We associate Paul b/c he ended up in the West. Wikipedia has interesting articles on the Middle Eastern and North African tradition
Jesus had no access to what we consider the Hebrew scriptures. I read that a Jew of his day would know the Torah, the Psalms, and the major prophets. Who knows what scriptures Nazareth may have used.
The early church believed in apostolic succession and the transmission of tradition. They were not Protestants with scriptures as the sole basis. Sermons were important. Local bishops writings were also used. A few bishops earned such praise and respect that their works travelled far and outsiders arranged to study with them. This area is not my profession. When I read the histories and commentaries, it appears to be a very fluid situation. Of course, Constantine wanted a unifying force. Recently, I reread Thomas Merton's collection of desert father sayings. The foreward describes the battles between Athanasius and Anthony. The Witnesses are such idiots with their WT devotion. If prominent early Christian fathers could have battles, JWN appears better.