The book of Acts continues the narrative of Luke's Gospel by tracing the story of the Christian movement from the resurrection of Jesus to the time when the apostle Paul was in Rome preaching the gospel unhindered. Most of the first half of Acts is occupied with the Jerusalem church and its relationships, while the latter half is dominated by Paul. The progress of the book is mainly geographical; from Jerusalem the word spreads to Samaria (8.5), the seacoast (8.40), Damascus (9.10), Antioch and Cyprus (11.19). Asia Minor (13.13), Europe (16.11), and finally Rome itself (28.16).
As in the Gospel of Luke (see Lk.1.1 n.), the author makes use of sources. The first half of Acts contains various traditions of the Jerusalem church and also a document which seems to reflect the interests of the church at Antioch (parts of chapters 6-8; 11.19- 30; 12.24-13.12; and perhaps other passages).
Much of the latter part of the book is narrated in the first person plural, beginning at 16:10. Many believe that Luke “the beloved physician” (Col. 4:14; 2 Tim. 4:11; compare Philem. 24) wrote these sections. Either his travel diary was incorporated in the work by someone else, or, more probably, he wrote both Luke and Acts, using the "we" style to indicate events of which he was an eyewitness.
Luke's purpose was to awaken faith by showing the triumphant progress of the Good News and to defend Christians against the charge that they were destructive of Jewish institutions and a troublesome element in the empire. But he had also an interest in history for its own sake and in the men and women of the story, in the details of lodging, entertainment, and travel, and all that constitutes local color. From every point of view, the New Testament would be infinitely poorer without this first book of church history.