Although the author does not name himself, evidence outside the Scriptures and inferences from the book itself lead to the conclusion that the author was Luke.
The earliest of the external testimonies appears in the Muratorian Canon (c. a.d. 170), where the explicit statement is made that Luke was the author
of both the third Gospel and the "Acts of All the Apostles." Eusebius (c. 325) lists information from numerous sources to identify the author of these books
as Luke (Ecclesiastical History, 3.4).
Within the writing itself are some clues as to who the author was:
Luke, the companion of Paul. In the description of the happenings in Acts, certain passages make use of the pronoun "we." At these points the
author includes himself as a companion of Paul in his travels (; --
; -- ;
see ; ).
A historian as careful with details as this author proves to be would have good reason for choosing to use "we" in some places and "they" elsewhere.
The author was therefore probably present with Paul at the particular events described in the "we" sections.
These "we" passages include the period of Paul's two-year imprisonment at Rome (ch. ). During this time
Paul wrote, among other letters, Philemon and Colossians. In them he sends greetings from his companions, and Luke is included among them
(see and ; ). In fact,
after eliminating those who, for one reason or another, would not fit the requirements for the author of Acts, Luke is left as the most likely candidate.
Luke, the physician. Although it cannot be proved that the author of Acts was a physician simply from his vocabulary, the words he uses and
the traits and education reflected in his writings fit well his role as a physician (see, e.g., note on ).
It is true that the doctor of the first century did not have as specialized a vocabulary as that of doctors today, but there are some usages in Luke-Acts that seem to suggest that
a medical man was the author of these books. And it should be remembered that Paul uses the term "doctor" in describing Luke
(see .
Date
Two dates are possible for the writing of this book:
(1) c. a.d. 63, soon after the last event recorded in the book, and
(2) c. 70 or even later.
The earlier date is supported by:
Silence about later events. While arguments from silence are not conclusive, it is perhaps significant that the book contains no allusion
to events that happened after the close of Paul's two-year imprisonment in Rome: e.g., the burning of Rome and the persecution of the Christians
there (a.d. 64), the martyrdom of Peter and Paul (possibly 67) and the destruction of Jerusalem (70).
No outcome of Paul's trial. If Luke knew the outcome of the trial Paul was waiting for (see ),
why did he not record it at the close of Acts? Perhaps it was because he had brought the history up to date.
Those who prefer the later date hold that reveals one
of the purposes Luke had in writing his history, and that this purpose influenced the way the book ended. Luke wanted to show how the church penetrated the world
of his day in ever-widening circles (Jerusalem, Judea, Samaria, the ends of the earth) until it reached Rome, the world's political and cultural center.
On this understanding, mention of the martyrdom of Paul (c. a.d. 67) and of the destruction of Jerusalem (70) was not pertinent. This would allow for the
writing of Acts c. 70 or even later.
Theme and Purpose
The theme of the work is best summarized in . It was ordinary procedure for a historian at this time to begin a
second volume by summarizing the first volume and indicating the contents anticipated in his second volume. Luke summarized his first volume in
; the theme of his second volume is presented in the words of Jesus: "You will be my witnesses in Jerusalem,
and in all Judea and Samaria, and to the ends of the earth"
(). This is, in effect, an outline of the book of Acts .
The main purposes of the book appear to be:
To present a history. The significance of Acts as a historical account of Christian origins cannot be overestimated. It tells of the founding
of the church, the spread of the gospel, the beginnings of congregations, and evangelistic efforts in the apostolic pattern. One of the unique aspects
of Christianity is its firm historical foundation. The life and teachings of Jesus Christ are established in the four Gospel narratives, and the book
of Acts provides a coordinated account of the beginning and spread of the church as the result of the work of the risen Lord and the Holy Spirit through
the apostles.
To give a defense. One finds embedded in Acts a record of Christian defenses made to both Jews
(e.g., ) and Gentiles (e.g., ),
with the underlying purpose of conversion. It shows how the early church coped with pagan and Jewish thought, the Roman government and Hellenistic
society.
Luke may have written this work as Paul awaited trial in Rome. If his case came to court, what better court brief could Paul have had than
a life of Jesus, a history of the beginnings of the church (including the activity of Paul) and an early collection of Paul's letters?
To provide a guide. Luke had no way of knowing how long the church would continue on this earth, but as long as it pursues its course,
the book of Acts will be one of its major guides. In Acts we see basic principles being applied to specific situations in the context of problems
and persecutions. These same principles continue to be applicable until Christ returns.
To depict the triumph of Christianity in the face of bitter persecution. The success of the church in carrying the gospel from Jerusalem to Rome and
in planting local churches across the Roman empire demonstrated that Christianity was not a merely human work. It triumphed under the rule
of the exalted Christ and through the power of the Holy Spirit.