In Luke's Gospel account, he emphasized the ministry of the HOLY SPIRIT in the life of CHRIST JESUS. However, in the Book of Acts, he emphasizes the role of the HOLY SPIRIT, in the growth and development of the early Christian Church in its infancy.
In the first century, the world was rife with myths, mystery religions and magic, and it was probably because of these confusions that Luke set out to more accurately record the facts of the origins of Christianity. He was intent on proving, through his Gospel account, and through this Book of Acts, that Christianity is not rooted in such myths and fables, but rather, has its roots in history, beginning with the birth of the Messiah in Palestine.