Acts of Apostles in the Early Church 

In his preface, Luke wrote two books. The first was his Gospel, also known as the "former book," and the second was Acts. Both are dedicated to Theophilus and written in the same Greek style.

Luke claimed he was writing accurate history of the church:

"Many have undertaken to draw up an account of the things that have been fulfilled among us, just as they were handed down to us by those who from the first were eye-witnesses and servants of the word. Therefore, since I myself have carefully investigated everything from the beginning, it seemed good also to me to write an orderly account for you, most excellent Theophilus, so that you may know the certainty of the things you have been taught."

 Referring to "things that have been fulfilled among us," Luke apparently is saying these events weren't random nor unexpected, but took place to fulfill Old Testament prophecy.

Next, Luke is talking about the apostles who witnessed the historical Jesus and who handed down to others what they had seen and heard.

Luke also personally researched events, "carefully investigating everything from the beginning."

Finally, he wrote an "orderly account" and addressed it to Theophilus and other readers.

Luke was well qualified to write history. He was an educated doctor and a cultured Greek, with a wide vocabulary and powers of observation. He was also Paul's traveling companion and had plenty of opportunity to hear and absorb the apostle's teaching and to write a personal travelogue of his experiences.

In addition, Luke lived in Palestine for about two years and gathered material through interviews for his Gospel and for Acts. He was familiar with Jewish history, customs and festivals, and visited places where Jesus and his disciples walked.

Many notable historians and archaeologists have defended the reliability of Luke's written account. Among them are Sir William Ramsey, the Scottish writer, who placed "the author of Acts among the historians of the first rank." A. N. Sherwin-White, of Oxford University, said that Luke's "historical framework is exact. In terms of time and place the details are precise and correct."

How did Luke go about writing his work as a historian and theologian?

From the prologue to his Gospel (1:1-4) one concludes he used written records and oral reports. Since the prologue is intended to cover both writings, it's reasonable to assume some information in Acts came from eyewitnesses as well.

This means by the time he composed Luke-Acts, Luke would have studied some written sources and contacted a number of individuals throughout the Mediterranean world about the history of the early church.

Much of the material in Acts comes from a number of different sources. One interpretation of the "we" sections indicates Luke obtained firsthand information while traveling with Paul.

The rest of Acts is made up of speeches (32 speeches, which add up to 25 percent of the book), travel narratives (38 percent of Acts) and many dramatic episodes.

Luke's theological agenda is a significant factor in the selection, arrangement and extent of his material in Acts, in much the same way that it governs the composition of his Gospel. Luke omits many of the apostles from Acts and devotes one-half of the book to Paul.

The speeches in Acts were not intended to be complete--not even the major ones by Peter (2:14-40), Stephen (7:2-53), and Paul in Athens (17:22-31) or during his defense before Felix (24:10-21), Festus (25:8-11) and Agrippa (26:2-23).

Luke also omits a significant amount of material about the history of the church. This may perplex us because other events, such as Paul's conversion (repeated three times), his deliberate turning from the Jews to the Gentiles and the continual rejection of the gospel by the Jews, are emphasized repeatedly.

This leads us to conclude that in writing his history, Luke made a deliberate and conscious selection of persons, places, speeches and events.

(Source: The Making of the New Testament by Arthur Patzia)