The Acts of the Apostles is the fifth book of theNew Testament which describes the founding of the Christian Church and the spread of the gospel message to the Roman Empire. . The author is generally believed to be Luke the Evangelist who was a doctor who travelled with the apostle Paul. The book is usually dated to around 80–90 AD. The first part including the events at Pentecost tells how God fulfilled his plan for the salvation of the world through the life, death, and resurrection of Jesus Christ. Acts then focusses on the story of the growth of Christianity in the first century, beginning with the acension of Jesus to Heaven. The early chapters, set in Jerusalem describe the coming of theHoly Spirit, the expulsion of Christians from Jerusalem and the establishment of the church at Antioch. Later chapters narrate the spread of the message under Paul the Apostle and concludes with his imprisonment in Rome, where he awaits trial.