Acts of the Apostles often referred to simply as Acts, is the fifth book of the New Testament; it tells of the founding of the Christian church and the spread of its message to the Roman Empire.

Acts and the Gospel of Luke make up a two-part work, Luke - Acts, by the same anonymous author, usually dated to around 80–90 AD. The first part, the Gospel of Luke, tells how God fulfilled his plan for the world's salvation through the life, death, and resurrection of Jesus of Nazareth, the promised Messiah. Acts continues the story of Christianity in the 1st century, beginning with Jesus's Ascension to Heaven.

The early chapters, set in Jerusalem, describe the Day of Pentecost (the coming of the Holy Spirit) and the growth of the church in Jerusalem. Initially, the Jews are receptive to the Christian message, but soon they turn against the followers of Jesus. Rejected by the Jews, under the guidance of the Apostle Peter the message is taken to the Gentiles.

The later chapters tell of Paul's conversion, his mission in Asia Minor and the Aegean, and finally his imprisonment in Rome, where, as the book ends, he awaits trial.

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