Several factors indicate that the writer of this Gospel was the same person who wrote the Book of Acts. First, a man named Theophilus was the recipient of both books (Luke 1:3; Acts 1:1). Second, Acts refers to a previous work by the same writer. Third, both books have several common themes some of which do not receive the same emphasis elsewhere in the New Testament. Fourth, there are general structural and stylistic similarities including the use of chiasms and the tendency to focus on specific individuals.
The writer also acquired his knowledge of Jesus' life and ministry from research rather than from eyewitness observations (Luke 1:1-4). Therefore he was not one of the disciples who travelled with Jesus.
The early church identified the writer as Luke. The heretic Marcion is the earliest witness we have to Luke's authorship (c. 135 A.D.). The Muratorian Canon (c. 180 A.D.) mentioned Luke as the writer too. It described him as the physician who accompanied Paul on his journey (cf. Acts 16:10-17; 20:5-15; 21:1-18; 27:1-28:16; Col. 4:14; Phile. 24; 2 Tim. 4:11). Irenaeus (c. 180-185 A.D.) also believed Luke wrote this Gospel and called him the "inseparable"companion of Paul.1Later church fathers referred to Luke as the writer of this Gospel. Luke was evidently a Gentile (cf. Col. 4:10-14).2Church tradition identified Antioch of Syria as Luke's hometown, but this is impossible to validate.
