Intriguing how the first-person plural passages in Acts led to speculation about the author of Luke and Acts. Was he or was he not Luke the physician, a companion of St. Paul? Were the passages from the author’s actual experiences, or did they draw on a travel diary by an unknown companion? Is use of the first-person simply a literary device?
Scholars disagree, notes Joseph Kelly (An Introduction to the New Testament, Page 183). Raymond Brown deems it possible the author of Luke-Acts did travel with Paul. Bart Ehrman favors the travel diary theory.
The passages are Acts 16:10-17, 20:5-16, 21:1-19 and 27:1-28:16.
“Personally,” Kelly says, “I find the travel diary theory unconvincing and the companion theory plausible but unprovable.” Ancient Christian writers who would have understood literary devices of the era believed the passages were written by the author.
Another interesting point: There’s only one mention in the Bible, in Colossians, that Luke was a physician. Scholars have not identified any passages in Luke-Acts that reveal any specialized medical knowledge.