This passage, accepted as authentic by many, must be declared doubtful, if not spurious, for the following reasons:
It is not quoted by the Christian fathers.
Tertullian was familiar with the writings of Tacitus, and his arguments demanded the citation of this evidence had it existed.
Clement of Alexandria, at the beginning of the third century, made a compilation of all the recognitions of Christ and Christianity that had been made by Pagan writers up to his time. The writings of Tacitus furnished no recognition of them.
Origen, in his controversy with Celsus, would undoubtedly have used it had it existed.
The ecclesiastical historian Eusebius, in the fourth century, cites all the evidences of Christianity obtainable from Jewish and Pagan sources, but makes no mention of Tacitus.
It is not quoted by any Christian writer prior to the fifteenth century.
At this time but one copy of the Annals existed and this copy, it is claimed, was made in the eighth century -- 600 years after the time of Tacitus.
As this single copy was in the possession of a Christian the insertion of a forgery was easy.
Its severe criticisms of Christianity do not necessarily disprove its Christian origin. No ancient witness was more desirable than Tacitus, but his introduction at so late a period would make rejection certain unless Christian forgery could be made to appear improbable.
It is admitted by Christian writers that the works of Tacitus have not been preserved with any considerable degree of fidelity. In the writings ascribed to him are believed to be some of the writings of Quintilian.
The blood-curdling story about the frightful orgies of Nero reads like some Christian romance of the dark ages, and not like Tacitus.
In fact, this story, in nearly the same words, omitting the reference to Christ, is to be found in the writings of Sulpicius Severus, a Christian of the fifth century.
Suetonius, while mercilessly condemning the reign of Nero, says that in his public entertainments he took particular care that no human lives should be sacrificed, "not even those of condemned criminals."
At the time that the conflagration occurred, Tacitus himself declares that Nero was not in Rome, but at Antium.
Many who accept the authenticity of this section of the "Annals" believe that the sentence which declares that Christ was punished in the reign of Pontius Pilate, and which I have italicized, is an interpolation.