The Book of Acts admits conflicts between Hebrews and Hellenists, and Jewish Christians and Gentile Christians, and Aramaic speakers and Greek speakers.
Gonzalez does a good job of drawing this out: "...a conflict between two groups of Jews: those who kept the customs and language of their ancestors, and those who were more open to Hellenistic influences. In Acts, the people in the first group are called 'Hebrews' and the others are the 'Hellenists'" (p. 25; emphasis added).
the Christian religion continued its spread throughout the Mediterranean Basin.[12] There is no agreement on how Christianity managed to spread so successfully prior to the Edict of Milan
Gonzalez makes a fascinating point on pages 17-18. He states that, "By the time of Jesus, there were sizable Jewish communities in every major city in the Roman Empire" (p.17). He goes on to say, "Diaspora Judaism is of crucial importance for the history of Christianity, for it was one of the main avenues through which the new faith expanded throughout the Roman Empire (p. 18)"