The author of Acts is not explicitely named, but from Luke 1:1-4 and Acts 1:1-3 we know that Acts and Luke were written by the same person. From Acts it is clear that the author was one of Paul's companions — sometimes he was part of events described (the so-called "we-sections"of Acts), other times not (referring to Paul's touring party as "they"). When we compare the events in Acts with information from Paul's letters, the only probable author is "Luke, the doctor", mentioned in Colossians 4:14. He was a Gentile, a medical doctor, and a "dear friend" and colleague of Paul.
The early Church Fathers unanimously ascribe Acts (and the Gospel of Luke) to Paul's doctor companion.
Why was it written?
If we accept the theory that Luke-Acts was written as a defence brief for Paul's attorney Theophilus, Acts is the second part, explaining how the teachings of a "Jewish prophet" became a world religion, and how it spread from Palestine to Rome, with particular emphasis on Paul's part in this. Luke could also have intended it as a history of Christianity's rapid growth over the then-known world, following the geographic strategy of Jesus in chapter 1:8: "Jerusalem, Judea, Samaria, ends of the earth". Most probably Luke had a double purpose: A brief for Theophilus and a history for the Church.
Acts is also the bridge between the Gospel accounts and the rest of the New Testament. It explains how the life and teachings of Jesus gave rise to the Church, and also introduces us to the writers of the rest of the New Testament — without it, we wouldn't know who Paul was, and why he wrote his letters.
It also provided a guide to the Church through history: Firstly by giving a model for the missionary work of the Church, secondly by providing the Church with a guide to "how to be" the Church, applying basic principles to various specific situations.
How and when was it written?
Acts is written with Rome as reference point: Places close to Rome are just mentioned, accepting that the reader is familiar with them; the further from Rome, the more Luke adds explanations and geographical information. Most probably it was written in Rome, shortly after the arrival of Paul and Luke, but before Paul's first trial before Caesar. The most probable date is 61-62 AD.
The book covers the first decades of the church, probably AD 30-62. Luke sourced his material from his own participation in Paul's travels, with the other parts filled in by Paul and his other companions.
First audience and destination:
Luke states in his introduction that his account was intended for Theophilus, but in all probability he also had the wider church in mind. After Theophilus the church in Rome would have been the next audience, and from there Luke's account spread through the wider Church.
Literary style:
· Luke uses a larger vocabulary than other New Testament writers, but adapts his word usage and and literary style to events and places he describes.
· He generally writes in excellent common ("Koine") Greek, but depending on the historical and other settings he could use classical Greek or reflect the underlying Aramaism language of Palestine.
· He presents a carefully structured account, including important early Christain speeches, various speakers and audiences, and various events, all set in authentic historical settings.
Special themes:
· God. We often think that the Holy Spirit features prminently in Acts, but in truth Acts focuses on the Trinity: The Holy Spirit focuses us on Jesus, and Jesus brings us back to the Father. (The Holy Spirit is mentioned 40 times in the first 13 chapters, God himself (Father) is mentioned 100 times!)
· Expansion. Acts is all about the growth of the church, from a small group of scared disciples to a worldwide phenomenon.
· Acts is a model for the church of all ages:
·· A manual for missionary activity. Wherever missions have followed the pattern of Acts, they have been successful
·· A model for church life. Read together with the Epistles, Acts gives us a blueprint for being God's community in this world.
Special features:
· Speeches. The use of speeches is a defining characteristic of Acts. Obviously these speeches are not verbatim reports, but accurate summaries of what was actually said (similar to today's concise newspaper reports of political speeches). At times Paul was apparently a long-winded preacher (20:7,9; 28:23), but his speeches can be read in a few minutes.
· Accurate historical detail. Acts is filled with sharp, precise details of countries, peoples, cultures, government institutions, court scenes etc. — yet archaeological findings confirm that Luke uses the proper terms for the time and place being described, and wherever it can be historically confirmed, his factual details are correct.
· Literary excellence. Acts is an excellent historical narrative, comparing well with other such works from antiquity.
· Dramatic description. Luke's account is vivid and fast-moving, using various speeches to build the drama, and his attention to detail brings the action to life. His account of the shipwreck en route to Rome, with its nautical details, is regarded as probably the best from ancient literature.
·Objectivity. Although Luke present a theological interpretation of historical events, his record is still factually accurate. He describes the good and the bad of the early church and the personalities involved, without taking sides or glossing over differences or divisions.
General structure:
Luke is structured around the two main apostles, Peter and Paul, but also reflects Jesus' strategy in Acts 1:8: The preaching of the gospel and the spreading of Christianity through the then-known world:
· Peter: Chapters 1-9:31 ·· In Jerusalem: Chapters 1-6:7
·· In Judea and Samaria: Chapters 6:8-9:31
· Paul: Chapters 9:32-28:31 ·· To the ends of the earth: Chapters 9:32-28:31
··· Gentiles and Antioch: Chapters 9:32-12:24
··· Asia Minor: Chapters 12:25-16:5
··· Europe: Chapters 16:6-19:20
··· Rome: Chapters 19:20-28:31