Regarding the issue of genuineness of Jesus of Whom the Four Gospel's teach, here is an excerpted portion of a discussion on the issues raised over the writings of Historian Joephus who lived at the time of the destruction of Jerusalem:
James Charlesworth writes: "Josephus must have made a reference to Jesus because the passage, divested of the obvious Christian words, is not Christian and is composed in such a way that it is very difficult to attribute to a Christian. What Christian would refer to Jesus' miracles in such a way that a reader could understand them as merely 'surprising works'? Would a Christian have written that 'first-rate men' or 'men of the highest standing amongst us' accused Jesus before Pilate, leaving the impression that he deserved a guilty verdict? Would a Christian scribe have ended a reference to Jesus by referring to 'the tribe of Christians' who 'are not extinct,' as if they should soon become extinct?" (p. 93)
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Concerning whether the passage leaves the impression that Jesus deserved a guilty verdict, Earl Doherty reaches the opposite conclusion: "The words and their context give the impression that the crucifixion was due to 'an accusation made by men of the highest standing among us,' that this was the execution of a wise and loved man, a teacher of truth who was obviously innocent. Nothing could better reflect the Gospel image. But that would mean that Pilate had acted improperly, or that he had been misled or coerced by others. There could be no basis on which Josephus would be led to interpret the event this way, much less put it in writing for a Roman audience. There would have been no channel through which such a judgment would come to him that he would have accepted. And no way he could have avoided explaining himself if he did." (p. 213)
Concerning the reference to "surprising works" (paradoxa erga), it is noted that Eusebius is one Christian who would refer to Jesus' miracles in this way (Ecclesiastical History 1.2.23). Also, if this phrase were used by Josephus, it would not in any way be diminutive. The same phrase is used by Josephus to describe the miracles of Elisha, for example (Ant. 9.182).