Josephus' Judean War, published as we know it in Greek around 75 CE, has been translated several time into languages like Latin. Sometimes the translations are quite close to the Greek, and more often than not are free paraphrases which omit some things and add others from alternate sources, such as his Judean Antiquities.
Well, one of these paraphrases was the version that was translated into old Church Slavonic around 1000 CE or a century or two later. However, it was SO WEIRD that some modern scholars were seriously suggesting it was either a FAKE (shades of Morton Smith's Letter to Theodore) or waved away as a medieval creation based on apocryphal gospels and such with ABSOLUTELY NO VALUE TO IT WHATSOEVER.
Unfortunately for everybody concerned, there are no easy answers to what it was based on. I suggested a couple in another thread (which was supposed to be about Eisenman, but I got my wires crossed, something that happens a lot now that I am "channeling God" as KK says).
Since the publishers of the Loeb classical library tend to release into the public domain the translations of works after the deaths of the translators, and this seems to have been the case with H. St. John Thackeray, who translated the books of the War, I think it is safe to give here the Appendix to his translation of the War that deals with the Slavonic version.
(Josephus) LCL 210, vol 3 of 9, The Jewish War, Books IV-VII (tr. by H. St. J. Thackeray, 1928)
I'll go book by book in the Greek text. These passages are confined to the first 4 books of the 5 volume Slavonic translation, which extend a bit into the 5th Greek volume. DCH APPENDIX
THE PRINCIPAL ADDITIONAL PASSAGES IN THE SLAVONIC VERSION
The first nineteen of these passages are translated from the German rendering of the Slavonic version produced by the late Dr. Berendts and Dr. Grass, Flavius Josephus vom Jüdischen Kriege, Buch i-iv, nach der slavischen Ubersetzung, Dorpat, teil i, 1924-1926, Teil ii, 1927; the last three passages from Dr. Berendts' translation in Texte und Untersuchungen, Neue Folge, vol. xiv, 1906. The history of these passages is obscure. They include some obvious Christian interpolations a; on the other hand, the Slavonic version, in which they are found, has been thought by some scholars to have preserved, at least in part, the author's original draft of the Jewish War. The reader is referred to a forthcoming work of Dr. Robert Eisler, "The Messiah Jesus and John the Baptist, as described in the unpublished 'Capture of Jerusalem' of Flavius Josephus and the Christian sources," of which an English edition will shortly be published by Messrs. Methuen, and an American edition by Lincoln MacVeagh (The Dial Press). The writer is greatly indebted to Dr. Eisler for assistance in the preparation of this Appendix. Notes which he has kindly supplied are indicated by the initials R. E.
635a Supposed interpolations, according to Dr. Eisler's critical edition of the text, are placed in square brackets in the following translation.
(1) Herod's Dream
[i. 328, inserted after προσημαίνουσιν.]
(But when Herod was in Antioch, he saw a dream which  revealed to him in advance his brother's death.) Now the dream was on this wise. There were four a ears of corn: the first was dry through frost, but the second stood upright, while wolves fell upon the third and cut (it) down and dragged it behind them. But the interpretation of it was on this wise. The first ear was Phasael, whom poisoning had dried up; the second ear was himself, inasmuch as he was b unscathed; while the third was his brother Joseph, whom warriors cut down and dragged away without burial. And his soul was stirred within him; at once terror seized him, and he went forth from the bed-chamber about midnight like one possessed. For the soul, which had understood sooner than the spirit, c was afraid. (And forthwith there came to him the melancholy tidings.)
636a So the text; but no further mention is made of the fourth.
b Lit. "is." According to Dr. Eisler, the present tense shows that the source was written while Herod the Great was still alive.
c Or "mind" (Geist).
(2) A Discussion OF Jewish Priests: "Herod is not the Messiah"
[Replacing i. 364-370 (middle) in the Greek.]
But Herod spent little (time) in Jerusalem, and marched against the Arabs. At that d time the priests mourned and grieved one to another in secret. They durst not (do so openly for fear of)e Herod and his friends.
For (one Jonathan) f spake: "The law bids us have no foreigner for king.g Yet we wait for the Anointed, the meek one,h of David's line. But of Herod we know that he is an Arabian, i uncircumcised. The Anointed will be  called meek, but this (is) he who has filled our whole land with blood. Under the Anointed it was ordained for the lame to walk, and the blind to see, a (and) the poor to become rich.b But under this man the hale have become lame, the seeing are blinded, the rich have become beggars. What is this? or how? Have the prophets lied? The prophets have written that there shall not want a ruler from Judah, until he come unto whom it c is given up; for him do the Gentiles hope.d But is this man the hope for the Gentiles? For we hate his misdeeds. Will the Gentiles perchance set their hopes on him? Woe unto us, because God has forsaken us, and we are forgotten of him! e And he will give us over to desolation and to destruction. Not as under Nebuchadnezzar and Antiochus (is it). For then were the prophets teachers also of the people, and they made promises concerning the captivity and concerning the return. And now — neither is there any whom one could ask, nor any with whom one could find comfort."
But Ananus the priest answered and spake to them: "I know all books.f When Herod fought beneath the city wall,g I had never a thought that God would permit him to rule over us. But now I understand that our desolation is nigh. And bethink you of the prophecy of Daniel; for he writes h that after the return i the city of Jerusalem shall stand for seventy weeks of years, which are 490 years, and after these years shall it be desolate." And when they had counted the years, (they) were thirty years  and four.a But Jonathan answered and spake: "The numbers of the years are even as we have said. But the Holy of Holies,b where is he? For this Herod he (sc. the prophet) cannot call the Holy one c—(him) the bloodthirsty and impure."
But one of them, by name Levi, wishing to outwit them, spake to them what he got d with his tongue, not out of the books, but in fable. They, however, being learned in the Scriptures, began to search for the time when the Holy one would come; but the speeches of Levi they execrated, saying, "Soup e is in thy mouth, but a bone in thy head," wherefore also they said to him that he had breakfasted all night and that his head was heavy with drink, as it were a bone. But he, overcome with shame, fled to Herod and informed him of the speeches of the priests which they had spoken against him. But Herod sent by night and slew them all, without the knowledge of the people, lest they should be roused; and he appointed others.
(And when it was morning the whole land quaked, etc., as in § 370 Greek text.)
636d Lit. "the."
e An apparent lacuna: words supplied by Berendts-Grass.
f The name, which has fallen out, is supplied from the sequel.
g Deut. xvii. 15.
h Zech. ix. 9.
i According to B.J. i. 123 he was an Idumaean; his friend Nicolas of Damascus represented him as belonging to one of the first Jewish families that returned from Babylon, Ant. xiv. 9; Christians called him a Philistine.
637 a Is. XXXV. 5 f.
b Cf. Is. Ixi. 1 (" to preach good tidings unto the poor ").
c sc. the rulership.
d Gen. xlix. 10: "The sceptre shall not depart from Judah . . . until Shiloh come: and unto him shall the obedience of the peoples be." Shiloh is interpreted above, as in the Targum, to mean "he whose it is."
e Cf. Is. xlix. 14, "Zion said, Jehovah hath forsaken me and the Lord hath forgotten me."
f i.e., of Scripture or of the Messianic Scriptures.
g Lit., "before the city," when besieging Antigonus in Jerusalem in 37 B.C., B.J. i. 343 ff.
h Dan. ix. 24 ff.
i Of the exiles from Babylon.
638 a This seems to mean that they reckoned that there were 34 more years still to run of the 490, within which, according to Daniel ix. 24, the Messiah was to appear. Berendts takes it to mean "Herod has 34 years to reign"; i.e., from his capture of Jerusalem in 37 B.C. to his death in 4 B.C. (cf. B.J. i. 665 ; Ant. xvii. 191). But we are not told that the priests were also prophets; this debate, moreover, is represented as taking place in the year of Herod's Arab campaign (3-2 B.C.), not in that of his accession (37 B.C). Herod was evidently dead when this chapter was written.
b Dan. ix. 24, "Seventy weeks are decreed ... to anoint a Holy of Holies." [The "Holy of Holies" is the last Messianic high-priest, cf. 1 Chron. xxiii. 13 : " Aaron was set aside for a holy one of holies " (literal trans, of MT.). R. E.]
vi. 69) is again the Messianic high-priest. R. E.]
d German festbekam. [for Greek ἔπηξεν. R. E.]
e Dr. R. Eisler would read "putty," thinking that the Greek reading underlying the Slavonic has arisen through confusion of maraq, "soup" and marqah, "putty."
 (3) Antipater's a Comparison of Himself to Heracles fighting the Hydra
[Replacing the sentence in i. 588, "Then there were these hydra heads, the sons of Aristobulus and Alexander, shooting up."]
But there are growing up against me and against my children the heads of the hydra (?). Just as Heracles sought to cut off the hundred heads of that beast with the sword, and, when he had not (yet) reached the last head, the heads again grew up, until he called Iolaus to his aid; (and as,) while Heracles hewed, Iolaus burnt out with a fire-brand the places that appeared through the gash, and thereby the growth of the heads of that beast was stayed — even so have I cut off Aristobulus and Alexander, but have gained no profit therefrom. For there are those who (stand) in their place, their sons, but I have no Iolaus to help me. And I know not how I should fulfil my desire.
639a Not "Herod's," as in Berendts-Grass (List of Contents).
(4) First Invective against the Romans (or Latins)
[Replacing i. 601-605.]
But Antipater, knowing nothing of these things, amused himself in Rome. And he lived just as becomes a king's son, alike in the magnificence of his surroundings, attendance and dress, and in munificence. Accordingly he gave large presents to the Roman authorities, and induced them to write in praise of himself to Herod.
And after receiving the presents, the [Italians, who are called] Latins wrote such praise of Antipater, as cannot be expressed, saying: "This man alone is thy defender and guardian and shield and deliverer from thy shameful sons. Had it not been for him, thy two first reprobate sons would have killed thee. And those two who are now here studying  philosophy clamour loudly against thee, reviling and representing thee as a monster."
For such are the Latins: they run to accept presents and break their oath for the sake of presents. And they see no sin in calumny, saying, "With words have we spoken, but we have not killed (anyone) ourselves," since the accursed wretches think that he is a murderer, who kills with the hand, but that calumny and denunciation and instigation against one's neighbour are not murder. Had they known the law of God, they would have been shown long since what a murderer is. a But they are aliens, and our doctrine a touches them not. Therefore did they lie against the two sons of Herod, who were then being educated in Rome, Archelaus (and) Philip, and wrote so that he should kill them.
But Herod, having fortified himself b against external things, and in consequence of the first painful inquiries, attached no credit to the Roman letters.
640a [Allusions to the rabbinic doctrine ('Arakin 15 b, Jer. Peah i. 16 a, etc.) that "calumny is threefold killing." It kills (in the end) the calumniator, the calumniated, and him who believes the calumny. R. E.]
b Lit. "his mind" (seinen Sinn).
(5) Second Invective against the Romans
[In i. 610, in place of the words παραχρῆμα μὲν ἔσπευδεν.]
(And during the time when he c was in Cilicia, he received his father's letter, of which we have spoken.) And he was highly delighted, and prepared a sumptuous dinner for his travelling companions and for the Romans, who through flattery had received from him three hundred talents.d
 For they are insatiable in receiving; but if anyone gives them more to-day, to-morrow they want (still) more. And as the sea cannot be filled, nor hell satisfied, nor woman's passion, even so are the Romans insatiable in receiving; in truth they are Solomon's leeches,a people who give their body and their soul for a reward. b Yet they are ready also to give up their limbs c and their brothers and children,d the former in that (by training) they convert boldness (and) fury into valour,e but the others in that they are covetous of gold, like ravens on a corpse. Many also for some trifle are prepared to surrender their (military) clothing, their cities, as also their generals.f We shall describe them in the sequel, but now we (will) relate the matter in hand.
(When Antipater came to Celenderis, etc.)
640c i.e., Antipater, on his homeward journey from Rome to Palestine.
d The Greek text in § 605 states that "his returns showed an expenditure of 200 talents" in Rome. The Slavonic omits that statement, but the 300 talents here mentioned may possibly have some connexion with that other sum.
641a An allusion to the Proverbs of Solomon xxx. 15 f., "The leech hath two daughters, Give, give. There are three things that are never satisfied . . . Sheol, and the barren womb, the earth that is not satisfied with water...." "Woman's passion" above (vice "the barren womb") follows the Lxx text (ἔρως γυναικὸς, xxiv. 51).
b [An allusion to the gladiatorial profession. Cf. Petronius 117 "tamquam legitimi gladiatores domino corpora animasque addicimus." R. E.]
c [An allusion to the auctorati, freeborn Romans entering the arena as gladiators for the sake of lucre. Cf. Tacitus, Ann. xiv. 14. R. E.]
d [An allusion to Romans selling their sons to the lanista, to be trained as gladiators. R. E.]
e die einen, indem sie durch (Zucht) Keckheit (und) Tollheit in Mannhaftigkeit verwandeln. [Cf. B.J. iv. 1. 6, § 45 τὸ ... τῆς ὁρμῆς [...] ἐμπειρίᾳ ... κατορθοῦμεν. He means the lanistae, the trainers of the gladiators' schools. R. E.]
f [The text has "and their clothing" at the end, but this makes a bad anticlimax. Dr. Eisler transposes the words and explains them as referring to deserters bartering away their outfit for civilian clothes and a little money.]
 (6) Moralizing on Divine Providence as exemplified in Abraham
[Following upon the trial and condemnation of Antipater, in place of i. 641-644.]
Therefore is it fitting to marvel at Divine Providence, how it requites evil for evil, but good for good. And it is impossible for man to hide from a His Almighty right hand, either for the just or for the unjust; but more still does His mighty b eye look upon the just. And indeed Abraham, the forefather of our race, was led out of his land, because he had offended his brother in the division of their territories c; and whereby he sinned, even thereby he received also his punishment. And again for his obedience d He gave him the promised land.e
b hochherrliches: cf. θεοῦ μέγας ὀφθαλμός, B.J. i. 84 and 378, where it is mentioned in conjunction with His right hand (οὐ διαφεύξονται τὸν μέγαν ὀφθαλμὸν αὐτοῦ καὶ τὴν ἀνίκητον δεξιάν).
c [An allusion to an otherwise unknown legend about Abraham depriving his brother Haran of his fair share of the land and consequently losing his own. According to Yacut ii. 231 the city of Haran was named after this brother of Abraham. In Ant. i. 7. 1 Josephus says that Abraham had to leave Mesopotamia, τῶν [...] Μεσοποταμιτῶν στασιασάντων πρὸς αὐτὸν [Ant. i. 157]. He does not wish to tell the Gentiles that it was a quarrel between Abraham and his brother Haran which drove him out of the country. R. E.]
d Gen. xii. 4.
e [This he shares fairly with Haran 's son Lot. R. E.]
(7) Appeal of the Rabbis Judas and Matthias quoting previous examples of heroism
[i. 650 : this fuller address in oratio recta replaces that in oratio obliqua in the Greek; the introduction also contains some additional words.]
For Herod had at that time erected a golden eagle over the great gate of the temple, in honour of the emperor;  and he called it the golden-winged eagle.a This the two (doctors) exhorted the people to cut down, saying: "Easy is it to die for the law of (our) fathers; for immortal glory will follow those who die thus,b while for their souls there awaits eternal joy. But those who die in unmanliness, loving the body, not desiring a manly death, but finding their end in sickness, these are inglorious, and will suffer unending torments in the underworld.c Forward, ye Jewish men! Now is the time to play the man. We will show what reverence we have for the law of Moses, in order that our people may not be put to shame, in order that we may not offend our lawgiver. For an example of heroism we have Eleazar d first, and the seven brethren,e the Maccabees, and their mother, who acted manfully. For Antiochus,f who had defeated and captured our country and domineered over us, was defeated by those seven striplings and by the aged teacher g and by the grey-haired woman. We, too, will show ourselves like them, that we may not appear weaker than the woman. But should we also be tortured for our zeal for God, then will our garland be yet better wreathed. But should they even kill us, then will our souls, after quitting the(ir) dark abode, pass over to (our) forefathers, where Abraham (is) and those (descended) from him."
643a The words "in honour . . . eagle'' are not in the Greek.
b Or " there " (da).
c Cf. B.J. vi. 46 ff., where, however, Titus speaks only of the "obliteration in subterranean night" and "oblivion" of those dying on a sick-bed, not of "unending torments."
d 2 Macc. vi. 18 ff.
e 2 Mace. vii.
g 2 Macc. vi. 18, "Eleazar, one of the principal scribes . . . well stricken in years."
(8) Herod's Sins and Punishment
[Replacing the last clause in i. 656, "His condition led diviners to pronounce his maladies a judgement on him for his treatment of the professors."]
For the eye of God looked invisibly upon his sins. He  had indeed defiled his dominion with bloodshed and with illicit intercourse with foreign women.a And because he had made others childless, therefore killed he also his children with his (own) hands;b and because he spared not his body in wantonness, therefore contracted he so foul a disease.
644a Or "with other men's wives."
b Cf. (6) above, for the punishment fitting the crime.