Inasmuch as many have undertaken to compile an account of the things accomplished among us, just as they were handed down to us by those who from the beginning were eyewitnesses and servants of the word, it seemed fitting for me as well, having investigated everything carefully from the beginning, to write it out for you in consecutive order, most excellent Theophilus; so that you may know the exact truth about the things you have been taught. Luke 1:1-4
So begins the Gospel of Luke, with a clear and definite purpose stated. Luke was not an eye-witness of these events, but he was a careful investigator who recorded the statements of those who were present. Luke was a physician and close companion of the Apostle Paul, and accompanied him on some of his journeys. He was an able researcher, for his two books (The Gospel and Book of Acts) are rich with detail.
The second part of Luke’s research, concerning the early days of the Christian movement, is recorded in Acts, for part of which Luke was actually present during the events. The introduction to that book states:
I wrote the first narrative, Theophilus, about all that Jesus began to do and teach until the day He was taken up, after He had given orders through the Holy Spirit to the apostles whom He had chosen. After He had suffered, He also presented himself alive to them by many convincing proofs, appearing to them during 40 days and speaking about the kingdom of God. Acts 1:1-3
Indeed some scholars speculate that the recipient of the letter, Theophilus (which means lover of God), was actually the defense counsel for Paul for his appearance before the emperor’s tribunal in Rome. If so, this letter was probably written in the late 50s or early 60s. It was obviously completed before the book of Acts, and A.D. 62 is the date of the latest event in that book, Paul’s house arrest in Rome. Just how early Luke began his research is unknown, but he spent time in Palestine during Paul’s imprisonment at Caesarea and could have started interviewing witnesses then. And of course, Luke also heard Paul speak many times about the things he heard from his conversations with the disciples in Jerusalem
Luke refers to others who compiled accounts. The Gospel of Mark appears to be one source he used. And due to the common material present in both the Gospels of Matthew and Luke but absent in Mark, scholars believe there was another document they call “Q” of which we do not have a copy.
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