Luke

Luke, the physician and travelling companion of Paul

held by the unbroken early tradition, with no rival name ever proposed in antiquity: Irenaeus, Against Heresies 3.1.1 (c. AD 180), 'Luke also, the companion of Paul, recorded in a book the Gospel preached by him'; the Muratorian Fragment, which names Luke the physician as the third Gospel's author; and Eusebius, Ecclesiastical History 3.4 (c. AD 325), who reports him an Antiochene by birth and a physician by profession

The argument from silence runs in this direction. A second-century church inventing an author for an anonymous book had apostles available and chose a man who was neither an apostle nor an eyewitness, and whose only claim was that he had done the research and travelled with Paul. Sir William Ramsay, who set out expecting to find a careless second-century compiler, ended by calling this writer 'a historian of the first rank' (St. Paul the Traveller and the Roman Citizen, 1895).

An anonymous writer of the second generation, with the 'we' passages inherited from a source

held by the mainstream critical reading, which accepts the unity of Luke and Acts but detaches the author from Paul: Joseph A. Fitzmyer (The Gospel According to Luke, Anchor Bible, 1981) and Raymond E. Brown (An Introduction to the New Testament, 1997), who read the first-person sections as material taken over from a travel diary rather than as the writer's own memory

The usual reason given is that the Paul of Acts is hard to line up with the Paul of the letters at certain points, particularly on the law and on the Jerusalem meetings. Fitzmyer himself kept the traditional name for the author while holding him at a distance from Paul's inner circle, so the two positions are closer than they are sometimes made to sound.

The medical vocabulary settles the physician question

held by William Kirk Hobart (The Medical Language of St. Luke, 1882), whose word lists were once treated as proof

This one has been fairly answered and the answer belongs on the page. Henry J. Cadbury (The Style and Literary Method of Luke, 1919) showed that most of Hobart's supposedly medical words appear in Josephus, Plutarch and Lucian, who were not physicians. The tradition that Luke was a doctor rests on Colossians 4:14, and it stands there without help from the word lists.

Written before about AD 62, while Paul was still in Roman custody

held by Adolf von Harnack, who changed his own mind late and argued the early date in The Date of the Acts and of the Synoptic Gospels (English translation 1911); John A. T. Robinson (Redating the New Testament, 1976); Colin J. Hemer (The Book of Acts in the Setting of Hellenistic History, 1989); and F. F. Bruce

The case is the ending of Acts. A writer who knew how Paul's trial came out, and who had watched Jerusalem burn, had every reason to say so and did not. Hemer added the observation that Acts uses provincial titles and administrative detail correct for the 50s and 60s and stale afterward.

Written between about AD 75 and 85

held by the majority of critical scholarship, including Fitzmyer (Anchor Bible, 1981) and Brown (1997)

Two arguments carry it. The first is literary: if Luke used Mark, and Mark is dated to the 60s, Luke must be later. The second is that the siege language of 19:43-44 and 21:20 is thought to reflect the events of AD 70 rather than to predict them, which turns on a prior judgment about predictive prophecy and is answered under The Hard Questions below.

Written in the second century

held by the older Tübingen reconstruction, and a smaller modern proposal that Luke is a reworking of the gospel Marcion used around AD 144

The manuscripts press hard against this. P75 carries most of Luke and John in a single codex and is dated on palaeographic grounds to roughly AD 175 to 225, which leaves almost no room for composition, revision, circulation and copying if the book were written in the 140s. The stronger form of the Marcion argument now runs the other way, treating Marcion's shorter gospel as an edited Luke.