reckoned his reign to begin A.D. 12, when Tiberius was associated by Augustus in the Empire. But such a method of reckoning the reign of Tiberius was unknown. According to Roman reckoning, Tiberius, in July A.D. 26, was either in his twelfth year (reckoning from the death of his predecessor) or in his twenty-eighth year (reckoning his tenure of the tribunician power). No other way of reckoning his reign was ever employed by Romans. How then could Luke speak of his fifteenth year ? There can hardly be any other reason than that the calculation was made under an Emperor whose years were reckoned from his association as colleague ; so that Luke, being familiar with that method, applied it to the case of Tiberius. Now that was the case with Titus. His reign began from his association with his father on 1st July A.D. 71.
We thus get a clue, though in itself an uncertain one, to suggest the date when Luke was at work. His chronological calculations were probably inserted as the finishing touches of Book I (p. 23), while Titus was reigning as sole Emperor, 79-81 A.D. ; and the com- position of that book belongs to the years immediately preceding, while the composition of Book II belongs to the years immediately following. This argument, taken by itself, would be insufficient ; but it is confirmed by the impression which the book as a whole makes. Acts could not have been written so late as Trajan, when long persecution had altered the tone and feeling of the Church towards the State. It is the work of a man whose mind has been moulded in a more peaceful time, and who has not passed through a time like the reign of Domitian (p. 22). On the other hand, its tone is not that of assured conviction about the relation to the State,
388 Composition and Date of Acts. Chap. XVII.
such as we observe in Paul's Epistles. It is the tone of one who seeks to prove a position that is doubtful and assailed, but still of one who believes that it may be proved. As we have seen, there runs through the entire work a purpose which could hardly have been conceived before the State had begun to persecute on political grounds. So long as Christians were proceeded against merely on the ground of crimes, which the accuser sought to prove by evidence (as was the case with Paul, p. 360), there was no necessity to establish that Christianity was legal. Defence then consisted in disproving the specific crimes charged against the individual Christian ; but, after the Flavian policy had declared Christianity illegal and proscribed the Name, the first necessity for defence was to claim legal right.
3. theophilus. It has an important bearing on Luke's attitude towards the Roman State that his work is addressed to a Roman officer,1 who had become a Christian. We may safely say tliat in the first century a Roman official would hardly bear the name Theophilus ; and therefore it must be a name given to him at baptism, and used or known only among the Christians. The fact that his public name is avoided, and only the baptismal name used, favours the supposition (though not absolutely demanding it) that it was dangerous for a Roman of rank to be recognised as a Christian. In the narrative of Acts there is not the slightest trace of private or baptismal
1 The epithet Kpdricrros is technical and distinctive, and not a mere usitata appdlatio hominum dignitute prcestantium, as even Blass takes it, on Acts XXIII 26. Luke uses it strictly there and in XXIV 3, XXVI 25, implying equestrian rank. Some Greeks were not so accurate a3 Luke.
Sec. 3. Theophiltis. 389
names. These seem to have been adopted under the pressure of necessity and from the desire for concealment. Thus the very dedication of the work points to a developed state of the relations between Church and State, and carries us down to the time of Domitian.