Isaac Abravanel (1437-1508] said:
« If Josephus wrote this, we don’t accept it from him, because he wrote a lot, but not everything is true »
Steve Mason tells us about 3 big issues with the “testimonium”
Geza Vermes says
« In contrast, proponents of the interpolation theory point out that testimonium contains blatant Christian statements (e.g., “He was the Christ”) that cannot be attributed to the Jew Josephus. »
Elisheva Carlebach and Jacob J. Schacter tell us that it is highly probable that eusebe modified the texts of Flavius Joseph, and that no church father before him spoke of the Testimonium.
Great video to watch : 
• https://youtu.be/Bi3opcRH7iU
• https://www.youtube.com/live/6Kt8mSCrXcU?feature=share
Richard Carrier thinks it is likely that Origen’s pupil, and Eusebius’s teacher – Pamphilus – was responsible for the interpolation in the TF.
https://freethoughtblogs.com/carrier/archives/4391 (it got suspended)
“This is a possibility Olson does not consider, but that I think deserves equal attention. My impression from the work of Eusebius is that he is kind of a doof and didn’t actually know where passages like this came from. I suspect he is not the forger. But Olson’s evidence entails that if Eusebius is not the forger, then his teacher and predecessor almost certainly is, and that’s Pamphilus of Caesarea. We have almost none of what was written by that man, thus we can’t check directly, but all the evidence Olson finds of Eusebian authorship of the TF could be remnants of vocabulary, idioms, and ideas Eusebius inherited from his teacher. And the timeline fits (I argue the accidental interpolation in the other passage occurred under Pamphilus’s watch as well, since it’s clear Eusebius didn’t know that had occurred, as I show in my article, yet it must have occurred after Origen, as I also show in my article, and Pamphilus was Origen’s successor; I also demonstrate there that all present copies of Josephus derive from the copy Eusebius held in his library, which was Pamphilus’s library, inherited from Origen).” This PDF concludes that none of it is authentic.
(3) Emmaus Narrative
(4) A Synopsis of the Testimonium and the Emmaus Narrative
(5) Coincidences of Structure
The coincidences with the Emmaus passage tend to support the second possibility. It seems less probable that two authors working independently would coincide to this extent, in light of the benchmark texts; as the Acts speeches demonstrate, even passages by a single author can take a variety of forms. If not due to a common source, these coincidences can have only two other explanations. Either they are due to chance; or the Testimonium is not, in fact, authentic, that it is the composition of a later Christian writer, and that this writer was in part influenced, directly or indirectly, by the excerpt from Luke.
(6) Coincidences of Textual Difficulties: Introduction
(2) The Testimonium phase could be a later Christian interpolation, influenced by Luke 24. This is Meier’s suggestion. In making his thorough analysis of the Testimonium style compared to those of the New Testament and Josephus, Meier commented on how unusual the construction was and presented Luke 24 as a partial parallel, noting that this and other “stylistic quirks” pointed to “a Christian interpolator or interpolators who naturally drew upon New Testament vocabulary as he (they) wrote about Jesus in his (their) own style.” Why it would be natural to draw on a single unique usage rather than the standard form is not at all clear. The Cleopas speech in itself makes only a marginal contribution to Christology, it is not very memorable, and I don’t believe it’s poetry resonates in one’s mind.
6.2 Coincidence at “Our Leaders”
A rare deviation from Josephus’ style is the lapse into first-person narration when discussing the accusers of Jesus: “the principal men among us.” In the Antiquities, as a rule, Josephus is careful to distance himself from his subject and refer objectively to “the Jews” rather than “us.” When there is an exception, there is usually an obvious explanation for it. Typically he will make a clear digression from the narrative to explain something about still-current Jewish customs, “our laws” or “our customs,” to his non-Jewish readers; or he may speak of the present and use ”our nation” when referring to the Jewish people after the war with Rome. But inserting himself implicitly into a historical narrative, as in the case of “the principal men among us,” is extremely rare. Similar phrases, but in the third person, appear quite frequently; for example, compare Ant. 14.9.3 §165, where the accusers at the trial of Herod are “the principal ones of the Jews.” Why the difference? This puzzle has been addressed by Testimonium commentators such as Thackeray and Winter, among others, without resulting in a reason for this collapse of authorial distance.
Here is the coincidence – the phrase at parallel location in the Emmaus narrative also employs the first person: “the chief priests and leaders of us.” Here the pronoun is justified because Cleopas and his companion are speaking – although they could have said “the leaders of the city,” or simply “the chief priests and leaders.” This expression does deviate from all other comparable speeches reported by Luke. In the speeches of Acts there is a concerted effort to disassociate the speaker from the leaders. In Acts 13:27, Paul, himself a dweller in Jerusalem, nonetheless asserts that “those dwelling in Jerusalem and their rulers” were the ones who asked Pilate to sentence Jesus. Note the pronouns in the speeches of Acts 2:23 (“you crucified”), 3:15 (“you delivered up”), 5:30 (“you laid hands on”), and 10:39 (“they did away with him”). Perhaps the first-person use in Luke 24 reflects or imitates an earlier, Jerusalem-centered tradition, whereas the speeches of Acts reflect the further development of the Church and the growing distance from its Jerusalem roots.
The explanations for this Luke-Testimonium coincidence are (1) chance, (2) the Testimonium phrase is a later interpolation, perhaps with polemical intent, influenced by Luke; or (3) that again, Josephus and Luke employed a similar source, and Josephus was careless in not changing the pronoun. There are, in fact, precedents for this sort of error. For example, the plea of Ezra in Ant. 11.5.3 §143 is reported as indirect speech and not as a quotation, yet refers to “our fathers;” Josephus seems to be speaking for himself. But that is certainly not Josephus’ intention; instead, he has accidentally copied over this phrase from the text on which he was drawing, namely, Ezra 9:7. The mistake is clear enough that Whiston’s translation alters it to read “their fathers.” The Testimonium usage may have be a similar error.
6.3 Coincidences of Terse Presentation
Every scholar of the Testimonium is vexed by its terseness. Josephus gives less information on the deeds and words of Jesus than he does for John the Baptist (Ant 18.5.2 §116-119), the impostor Theudas (Ant. 20.5.1 §97-99), and any number of other individuals. The same question applies if the entire passage is supposed to be the effort of a Christian forger, for would not a Christian have an interest in being clear and direct concerning the historical Jesus? Where the Testimonium is terse, so is the Emmaus narrative, and, more significantly, at such points there are similarities of presentation and vocabulary, although a variety of other expressions could have been used. Here I will comment on three of these points. Deeds. Commentators have wondered why Josephus did not simply say “healings,” or something similarly expressive, rather than the enigmatic “deeds” with its difficult adjective surprising (or wonderful, unusual, incredible). Luke parallels Josephus with the equally uninformative “mighty in deed.” Commentators have pointed out that ”deeds” here may have a special, understood connotation of magical acts.
A nearly identical phrase is used by Josephus concerning Elisha (Ant. 9.8.6 §182), albeit only after detailing several of the miracles. There is also a passage from the Mishna that applies the term “men of deed” to people in the category of the miracle-worker Chanina ben Dosa (M. Sotah 9:15). Geza Vermes suggests the use of “deed” by both the Testimonium and Luke 24:19 may reflect this special meaning.16 The puzzle is why both Josephus and Luke used only this word, coupled with one strong adjective, to cover the acts of Jesus. It might also be significant that the phrase “word and deed” in Luke, although apparently conventional, nonetheless appears in reverse order the seven other places in the News Testament it is used, such as Acts 7:22 (Moses is mighty “in words and in deeds”); and only once, in Jude, as it is in Luke. Therefore this order, the same as the Testimonium, cannot quite be taken for granted. The prophets. In both texts, the predictions of the prophets, which occur at the end of the passages, are divided into two parts. (1) The prophets are first said to have told predictions that explain “these things” (τα˜υτά in both), referring to the preceding accounts. In Josephus, “the prophets of God had foretold these things;” in Luke, “all which the prophets have spoken. Must not the Messiah suffer these things…?”
Louis Feldman:
That the passage is, indeed, interpolated seems indicated by the fact that in the statement in the War about the deeds of Pilate, which parallels this in the Antiquities, there is no mention of Jesus, despite the fact that the length of the account is almost as great as that in the Antiquities. In addition, Justus of Tiberias (ap. Photius, Bibliotheca 33), Josephus’ great contemporary and rival, apparently made no mention at all of Jesus. The fact that an ancient table of contents, already referred to in the Latin version of the fifth or sixth century, omits mention of the Testimonium (though, admittedly, it is selective, one must find it hard to believe that such a remarkable passage would be omitted by anyone, let alone by a Christian, summarizing the work) is further indication that either there was no such notice or that it was much less remarkable than it reads at present. Furthermore, it is not cited until Eusebius does so in the fourth century, despite the fact that such a passage would have been extremely effective, to say the least, since it comes from a Jew who was born only a few years after Jesus’ death, in the debates between Jews and Christians, especially since we know that Justin Martyr (Dialogue with Trypho 8) attempted to answer the charge that Jesus had never lived and that he was a mere figment of Christian imagination.
And yet, I have counted no fewer than eleven church fathers prior to or contemporary with Eusebius who cite various passages from Josephus (including the Antiquities) but who do not mention the Testimonium. Moreover, during the century after Eusebius there are five church fathers, including Augustine, who certainly had many occasions to find it useful and who cite passages from Josephus but not this one. It would also seem remarkable that Jerome, who does cite the passage (De Viris Illustribus 13. 14), says that Jesus was believed (credebatur) to be the messiah, and not, as Josephus has it in our text, that he was the messiah. Moreover, though Jerome knows Josephus so well that he cites him no fewer than ninety times and, indeed, refers to him as a second Livy (Epistula ad Eustochium 22), he cites the Testimonium only this one time. To be sure, all this is the argumentum ex silentio, but as a cumulative argument it has considerable force.
Josephus, Judaism, and Christianity Brill 1987 pg. 57
> *One of the problems, however, with regard to Eusebius’ role in connection with our Testimonium is that he quotes it differently in the three places where he mentions it. The simple explanation for this would be scribal modification or error in the transmission of the text, though this must always be a last resort in textual criticism. More likely, the divergent versions are due to the difficulty that the writers in antiquity had in consulting original texts and their consequent greater reliance upon memory…*
Geza Vermes:
The Christian passages, those that cannot be ascribed to the Jew Josephus, are easily distinguishable. The gloss, “If indeed one ought to call him a man”, is the interpolator’s reaction to the superhuman/divine Jesus being called a mere “wise man”. “He was the Christ” is a common Christian interpolator’s confession of the messianic status of Jesus. Nevertheless, the original text must have contained the epithet, “Christ”, to account for the later statement about “the tribe of the Christians” named after the founder. The most likely original version read, “He was called the Christ”, as Josephus puts it in the James passage. The reference to Jesus attracting to himself “many Greeks” is without Gospel support. Nevertheless, if Josephus knew of a mixed Jewish-Gentile church in Rome, he may have believed that a similar structure existed at the time of Jesus. The resurrection appearances on the third day, together with the relevant prophecies, are part of the apologetic arsenal of the early church and have nothing to do with Josephus.
For Old Testament reliability of Josephus, Feldman discusses:
Factors That Influenced Josephus in His Rewriting of the Bible
Josephus ‘Non-Jewish Audience
Josephus’Jewish Audience
Concern with Assimilation and Intermarriage
Respect for the Prophets
Regard for the Priesthood and Especially for the Temple in Jerusalem
Concern to Show That His Biblical Heroes Are Fully Comparable to Pagan Heroes
a. Good Birth
b. Precociousness
c. Handsome Stature
d. Wealth
e. Wisdom
f. Courage
g. Temperance
h. Justice (including especially respect for truth, humanity (…), mercy, hospitality, gratefulness, and generosity)
i. Piety
Qualities of Leadership
Importance of Repentance
Respect for Law and Order
Respect for the Concept of a Just War
Contempt for the Masses
Disdain for Demagogues
Realistic Attitude and Even High Regard for the Superpower of the Day
Opposition to Messianic and Messianic-like Movements
Contempt for the Revolutionaries of His Own Day
Abhorrence of Civil Strife
Loyalty to Rulers
Loyalty to Mentors and Friends
Tolerance and Respect toward Non Jews and Especially Non Jewish Leaders
Tolerance toward Non Jewish Religions
Insistence that Gentiles Do Not Hate Jews
Compliments by Non-Jews
Concern to Refute the View That Jews Are Aggressive in Seeking Converts
Insistence that Jews Are Not Busybodies
Establishment of the Historicity of Biblical Events
Improvements in the Narrative through Removal of Difficulties and Contradictions
Stylistic Improvements
Hellenization of the Narrative for His Greek Readers
Increased Suspense, Drama, and Irony
Derogatory View of Women
Increased Romantic Element
Introduction of Wise Sayings
Appeal to Philosophic Interests
Interest in Military Details
Analysis of the True Motives of People
G-d’s Reward for Those Who Obey His Laws and Punishment for Those Who Do Not
De-emphasis on G-d’s Role in History
De-emphasis on Miracles
Resolution of Theological Problems