In the first four verses of the Gospel of Luke, readers encounter a unique prologue that states Luke’s purpose and method in writing his Gospel. He has used previous written accounts of Jesus’ life, he has accessed the testimony of eyewitnesses, and he has taken great care to organize all of this material into an orderly account so that an individual named Theophilus may know the truth.
The way Luke begins his Gospel suggests that he regarded himself as a historian. Indeed, Luke’s prologue is similar to other introductions found in ancient texts, and scholars generally classify these as belonging to the Greco-Roman genre of history.
But we shouldn’t assume that ancient writers meant the same thing by “history” that we mean today. In his History of the Peloponnesian War, the fifth-century B.C.E. Greek writer and ancient historian Thucydides reveals something interesting: although he tried his best to accurately reproduce speeches that generals and other leaders made, this was not always possible. In such cases, Thucydides invented speeches based on what he imagined the leaders must have needed to say under the circumstances.
Fabricating speeches would, of course, have significant repercussions for any professional historian today—such as being stripped of his or her Pulitzer Prize. Nevertheless, mixing fact and fiction was considered entirely appropriate in antiquity. An awareness of these principles of ancient history writing should make us extremely cautious about supposing that the author of the Gospel of Luke is anything like our modern conception of a historian.
When we look closely at Luke’s Gospel, we find a mix of solid historical data and imaginative reconstruction. Let’s consider Luke 13:1-5 to investigate Luke’s knowledge of historical sources. In this little-studied passage, Jesus discusses the meaning of two tragic recent events: Pontius Pilate’s shocking execution of some Galileans who were offering sacrifices at the Jerusalem temple, and the collapse of the tower of Siloam that killed eighteen people. Neither of the events mentioned in Luke 13:1-5 are attested in any other sources, but they are both very likely to have happened because they are relatively routine occurrences: Pilate behaved brutally on numerous occasions, and buildings collapse. To be aware of two quite minor events that took place in Jerusalem in the 20s C.E., Luke must have had access to some very reliable sources—perhaps even eyewitnesses.
On the flip side, Luke reports some events that strain his credibility. A prominent example is Luke 2:1-7, the worldwide census ordered by Emperor Augustus when Quirinius was governor of Syria, an event that purportedly brought Joseph and a pregnant Mary to Bethlehem.
First, we have no external evidence of the Romans conducting an empire-wide census; rather, we know censuses were always administered at the level of individual provinces. Second, Luke is correct that a census of the Roman province of Judea was undertaken under Quirinius. However, Quirinius began his appointment in the year 6 C.E., whereas Luke 1:5 strongly implies that Jesus was born before the death of Herod the Great in 4 B.C.E. So there is a 10-year gap between when Luke says Jesus was born and Quirinius’s census. Third, a census requiring everyone throughout the Roman Empire to return to his or her place of origin to pay taxes would have been a logistical nightmare. Certainly the Romans were cruel, but they were also efficient.
So how do we account for a Gospel that is believable about minor events but implausible about a major one? One possible explanation is that Luke believed that Jesus’ birth was of such importance for the entire world that he dramatically juxtaposed this event against an (imagined) act of worldwide domination by a Roman emperor who was himself called “savior” and “son of God”—but who was nothing of the sort. For an ancient historian following in the footsteps of Thucydides, such a procedure would have been perfectly acceptable.