What does Acts 2:10 mean?

About 900,000 Jews have come to Jerusalem from all over the Roman Empire and the Middle East to celebrate Pentecost. On the day of the celebration, they're astounded to find 120-or-so Galileans speaking in the visitors' native dialects. Luke mentions the general areas from which these travelers came, starting with the Middle East and modern-day Asia Minor in Acts 2:9. Here, he continues.

Phrygia is an amorphous geographical area with ever-changing borders west of central modern-day Asia Minor. Sometimes Asia, the large province to the west, claimed it, and sometimes Galatia, the large province to the east, claimed it. At the time of Paul's travels, it seems to have been somewhat split, with some regions being considered "Asia," and others not (Acts 16:6).

Pamphylia is easier to recognize as it is along the southern-central shore of modern-day Asia Minor. Today, it is home to the Turkish resort town Antalya. In the time of Luke, it was convenient because it is directly north of Alexandria, Egypt. Rome depended on the grain from Egypt; great ships would sail north from Alexandria to Pamphylia and then west to Italy (Acts 27:6).

Luke's list, "Cappadocia, Pontus and Asia, Phrygia and Pamphylia" (Acts 2:9–10) swoops from eastern present-day Asia Minor, up across the north, down the west coast, and to the southern coast. He skips southeastern Cilicia and central Galatia, but the overall effect is that the entire peninsula is included.

Egypt and Libya encompass much the same territories they do today in the eastern half of the northern coast of Africa. Alexandria in Egypt was home to the largest Jewish community in the world. Cyrene is known as the hometown of Simon who helped Jesus carry His cross (Luke 23:26).

Finally, Luke skips over Greece and Macedonia, which have minimal Jewish settlements, and mentions Rome. It's unclear what effect the Pentecost event has on the Jews in Rome. Priscilla and Aquila are from Rome and meet Paul in Corinth (Acts 18:2), but the text doesn't say if they were Christians before they met Paul. Years later, when Paul finally reaches Rome and starts his first Roman imprisonment, he meets with the Jewish leaders from the synagogue. They know of "The Way," and know that many speak against it, but beyond that, they don't seem to know what it's about (Acts 28:17–22). Judaism, however, did spread among the Gentiles in Rome.