The name Lucas (Luke) is probably an abbreviation from Lucanus
Luke was a native of Antioch.
Luke was not a Jew
Luke had a great knowledge of the Septuagint and of things Jewish, which he acquired either as a Jewish proselyte (St. Jerome) or after he became a Christian, through his close intercourse with the Apostles and disciples. Besides Greek, he had many opportunities of acquiring Aramaic in his native Antioch, the capital of Syria. He was a physician by profession, and St. Paul calls him "the most dear physician" (Col., iv, 14). This avocation implied a liberal education, and his medical training is evidenced by his choice of medical language. Plummer suggests that he may have studied medicine at the famous school of Tarsus, the rival of Alexandria and Athens, and possibly met St. Paul there. From his intimate knowledge of the eastern Mediterranean, it has been conjectured that he had lengthened experience as a doctor on board ship. He travailed a good deal, and sends greetings to the Colossians, which seems to indicate that he had visited them.
Acts 16:10 Luke begins using first person plural.
It is worthy of note that, in the three places where he is mentioned in the Epistles (Col., iv, 14; Philem., 24; II Tim., iv, 11) he is named with St. Mark (cf. Col., iv, 10), the other Evangelist who was not an Apostle (Plummer), and it is clear from his Gospel that he was well acquainted with the Gospel according to St. Mark; and in the Acts he knows all the details of St. Peter's delivery--what happened at the house of St. Mark's mother, and the name of the girl who ran to the outer door when St. Peter knocked. He must have frequently met St. Peter, and may have assisted him to draw up his First Epistle in Greek, which affords many reminiscences of Luke's style
The style of the Gospel is superior to any N. T. writing except Hebrews.
"The author of the Third Gospel and of the Acts is the most versatile of all New Testament writers. He can be as Hebraistic as the Septuagint, and as free from Hebraisms as Plutarch. . . He is Hebraistic in describing Hebrew society and Greek when describing Greek society" (Plummer, introd.). His great command of Greek is shown by the richness of his vocabulary and the freedom of his constructions.
Thus the external evidence is both unanimous and early. “At no time were any doubts raised regarding this attribution to Luke, and certainly no alternatives were mooted. The tradition could hardly be stronger . . .”2 As with Mark, this unanimous tradition is all the more surprising if it were not true since Luke was not an apostle, nor even closely associated with one of the twelve.
Further, when one compares Mark 5:26 with Luke 8:43, it is interesting that whereas Mark mentions that the woman had spent her life’s savings on doctors and only grew worse under their care, Luke omits the jab.
Acts is to be dated c. 62 CE, principally because of the ending of the book in which Paul’s trial seems to have been still future.
It is possible to view the name as symbolic (“lover of God,” or “loved by God”), as if the real addressee needed to be incognito for some reason. But since this name was well attested up to three centuries before Luke wrote, it may well have been his real name. If Theophilus was a Roman official, then he certainly was a Gentile, and the contents of this gospel, as well as the Acts, bear eloquent testimony of a Gentile readership.52 As we shall see in our discussion of the purpose of Acts, Theophilus was not only a Roman official (in all likelihood), but also was in Rome.
Thus in a masterful series of Seven Books, Luke has not only shown how the Church grew from its humble beginnings, but he has also vindicated both Paul’s apostleship and his innocence. His literary labors to get Paul free were successful: the apostle to the Gentiles was released; he ministered for three more years and wrote three more epistles before his beheading.