Easton's Bible Dictionary (1897)
Lover of God, a Christian, probably a Roman, to whom Luke dedicated both his Gospel (Luke 1:3) and the Acts of the Apostles (1:1). Nothing beyond this is known of him. From the fact that Luke applies to him the title “most excellent”, the same title Paul uses in addressing Felix (Acts 23:26; 24:3) and Festus (26:25), it has been concluded that Theophilus was a person of rank, perhaps a Roman officer.
Smith's Bible Dictionary (1863)
(friend of God) the person to whom St. Luke inscribes his Gospel and the Acts of the Apostles. (Luke 1:3; Acts 1:1) From the honorable epithet applied to him in (Luke 1:3) it has been argued with much probability that he was a person in high official position. All that can be conjectured with any degree of safety concerning him comes to this, that he was a Gentile of rank and consideration who came under the influence of St. Luke or under that of St. Paul at Rome, and was converted to the Christian faith.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
THEOPH'ILUS (lover of God), a distinguished individual, probably of Greece or Rome, to whom, as his particular friend or patron, Luke addressed both his Gospel and his history of the Acts of the Apostles. Luke 1:3. The title "most excellent" probably denotes official dignity. Acts 23:26; 1 Sam 24:3; and Gen 26:25.
Hitchcock's Bible Names (1869)
friend of God