Acts 6-8 describe the activities of two non-apostles, Stephen and Philip. Both are Hellenistic Jews, and neither is numbered among the Twelve. It is possible these men were not followers of Jesus prior to Pentecost. Perhaps they were among the crowd who hear Yet Stephen is the first martyr and his speech summarizing some important theological points in the transition between Peter’s ministry in Jerusalem and Paul’s mission in Acts 13. Philip is the evangelist who brings the Gospel to Samaria and to an Ethiopian, perhaps fulfilling the commission in Acts 1 to go to Samaria and the “ends of the earth.”
This section is sometimes cited as an example of Luke creating a story in order to describe a smooth transfer of leadership from the Jewish followers of Jesus to the Hellenistic Jewish followers. But things are not as smooth as they appear. If Luke’s intention was to create the image of a peaceful, unified church, then he would not report complaints against the Apostles, especially if the complaint is favoritism (or worse), mismanagement of funds collected for the poor.
Acts 6:1 says that there was a problem between “Hebraic” and “Hellenistic” Jews. This needs to be explained carefully, since the word “Jew” does not appear in the text (although English translations regularly include it). Obviously these are all Jews, but there seems to be problem between the Jews who are in Jerusalem from “outside” and those Jews who remained on “the inside.” Chapters 6-8 concern the activities of two Hellenistic Jews and their ministry outside of the circle of the apostles in Jerusalem. I would suggest here that Luke has intentionally arranged several stories concerning Peter and John in chapters 2-4, and several stories concerning Stephen and Philip in chapters 6-8.
This is not necessarily a geographical division, although doubtless it often was. To be a “Hellenist” was to adopt the language and culture of the Greeks, while to be a “Hebrew” was to adopt a more tradition Jewish language and lifestyle. For Ben Witherington, language is the main issue (see Acts 240-247, for an excellent excursus on the Hellenists). Bock, on the other hand, agrees more with my sketch of the Hellenists (Acts, 258-9). Language is an important issue, but it is not the only issue separating the Greek from Judean Jew.
Aside from historical accuracy, does this matter for reading Acts? I think it helps understand that the community of earliest believers were far more diverse than Acts 2-5 would imply. If Peter and John represent the only form of the early followers of Jesus, then it is hard to explain the violent suppression of Stephen. This diversity is less a “development” in the earliest church, but a factor present from the beginning.