Here are the actual quotes in question. The first is from Antiquities 11:1 where Josephus counts 70 years from the time the "poor people" went off their land, that is, in year 23 of Nebuchadnezzar at the time of the last deportation (Jer. 52:30). He further applies the fulfillment of Jeremiah's prophecy to this specific seventy years and does not mention "desolation" but "servitude." Following that are the two quotes in his later work, "Against Apion" where he first mentions the seventy years and then mentions "fifty years" just two paragraphs later. a seeming contradiction unless his second reference was related to the fifty years ending when Cyrus first became king of Persia and not after 70 years when he became king at Babylon. These two dates are currently 559 and 539BCE for the rulerships of Cyrus.
"ANTIQUITIES" 11:1:11. IN the first year of the reign of Cyrus (1)
which was the seventieth from the day that our people were removed out of their own land into Babylon, God commiserated the captivity and calamity of these poor people, according as he had foretold to them by Jeremiah the prophet, before the destruction of the city, that after they had served Nebuchadnezzar and his posterity, and after they had undergone that servitude
seventy years, he would restore them again to the land of their fathers, and they should build their temple, and enjoy their ancient prosperity.
AGAINST APION, 1:19
And when he was relating the acts of this king, he describes to us how he sent his son Nabuchodonosor against Egypt, and against our land, with a great army, upon his being informed that they had revolted from him; and how, by that means, he subdued them all, and set our temple that was at Jerusalem on fire; nay, and removed our people entirely out of their own country, and transferred them to Babylon; when it so happened that our city was desolate during the interval of
seventy years, until the days of Cyrus king of Persia.
AGAINST APION 1:21
21. These accounts agree with the true histories in our books; for in them it is written that Nebuchadnezzar, in the eighteenth["nineteenth" in other copies] year of his reign, laid our temple desolate, and so it lay in that state of obscurity for
fifty years; but that in the second year of the reign of Cyrus its foundations were laid, and it was finished again in the second year of Darius. I will now add the records of the Phoenicians; for it will not be superfluous to give the reader demonstrations more than enough on this occasion. In them we have this enumeration of the times of their several kings: "Nabuchodonosor besieged Tyre for thirteen years in the days of Ithobal, their king; after him reigned Baal, ten years; after him were judges appointed, who judged the people: Ecnibalus, the son of Baslacus, two months; Chelbes, the son of Abdeus, ten months; Abbar, the high priest, three months; Mitgonus and Gerastratus, the sons of Abdelemus, were judges six years; after whom Balatorus reigned one year; after his death they sent and fetched Merbalus from Babylon, who reigned four years; after his death they sent for his brother Hirom, who reigned twenty years. Under his reign
Cyrus became king of Persia." So that the whole interval is
fifty-four years besides three months; for in the seventh year of the reign of Nebuchadnezzar he began to besiege Tyre, and Cyrus the Persian took the kingdom in the fourteenth year of Hirom. So that the records of the Chaldeans and Tyrians agree with our writings about this temple; and the testimonies here produced are an indisputable and undeniable attestation to the antiquity of our nation. And I suppose that what I have already said may be sufficient to such as are not very contentious.
JOSEPHUS PLAYING NUMBERS GAMES: Just an added note here. Some believe that the references to the 13-year seige of Tyre was a cryptic way Josephus had of making reference to the fall of Babylon within the 20-year rule of Cyrus. Here's how that theory works. It's a game of substitution. Cyrus gets substituted for Hirom and Babylon for Tyre, Cyrus for Darius, all mentioned here. The various numbers are 54 years, the "nineteenth" of Nebuchadnezzar when Jerusalem fell, Cyrus taking the kingdom in the 14th year of Hirom.
First of all, please note if this entire period of 54 years from the fall of Jerusalem or fifty years from the last deportation as per Josephus' previous reference is applied until the time that Cyrus takes the kingdom, then Cyrus whould have become king at the end of this 54 and 50-year period which would including the entire 20-year rule of Hirom. Which doesn't work. Intead, he claims Cyrus took the kingdom in the 14th year of Cyrus.
But note how these numbers work out when compared to the actual chronology. Cyrus took over Persia when he conquered Astyages in the 5th year of Nabonidus, that means he became king in Babylon in his 21st year counting from year 1. But if you count 20 years from the 7th year of Nabonidus, then he becomes king in his 20th year from year 7. This is the interval assigned to the reign of Hirom, 20 years beginning year 7 of Nebuchadnezzar.
Only Jospheus is pulling our legs here since Hirom was well-known to the Jews to be a king during the time of Solomon. But note what happens when you date events based upon 20 years beginning year 7 of Nabonidus which is substituted for Nebuchadnezzar. The 13-year siege of Tyre beginning year 7 is precisely the year Babylon falls in relation to year 7 of Nabonidus, followed by Darius the Mede coming to the throne for 6 years.
With this information, we can determine just how long Nabonidus ruled before Darius the Mede's 6-year rule based upon the 20 years of Cyrus as king of Persia. Subtract 6 years from 20 and that leaves you 14 years. 14 plus 5 is 19 years. Of course, 14 years from year 6 of Nabonidus is the same as 13 years from year 7, the length of the siege of Tyre.
So in other words, if you count 20 years beginning year 7 of Nabonidus to represent the 20 year rule of "Hirom" then Babylon falls in the 13th year and Darius the Mede becomes king in his 14th year. Which is too much of a coincidence not to suspect that this was Josephus' way of secretly giving us the lost of chronology of the last 20 years of Cyrus, especially in relation to "Darius" (who is mentioned) and the fall of Babylon which is being referenced as the fall of Tyre. Here is a rough timeline for those two years so you can see how it works -- it's kind of hard to explain.
A
01----------Nabonidus begins his rule
02
03
04
05
06------Year 6 Cyrus begins 20-year rule
07-----01 Year 7 begins 20-year of "Hirom" and 13-year seige of Tyre, only meaning Babylon
08-----02
09-----03
10-----04
11-----05
12-----06
13-----07
14----08
15----09
16---10
17----11
18----12
19----13th year of seige Babylon falls, 13th year of Hirom
01----14th year of Hirom "Cyrus takes kingdom" only it's "Darius" beginning 6-year rule
02---Year 2 Darius the Mede, 15th of Hirom
03---Year 3 Darius the Mede, 16th of Hirom
04----Year 4 Darius the Mede, 17th of Hirom
05----Year 5 Darius the Mede, 18th of Hirom
06----Year 6 of Darius the Mede, 19th of Hirom
01---Year 1 of Cyrus over Babylon, 20th of Hirom
The cryptic references are "54" being the number of years from the fall of Jerusalem until when Cyrus first became king of Persia.
The cryptic reference for "50 years" is the time of the last deportation until Cyrus first becomes king in Persia.
Counting from year 7 of Nabonidus, Babylon falls in year 13, and a kingship occurs in year 14. Darius the Mede began his official rule in the 14th year after the 7th year of Nabonidus.
The above comparison might seem far out, but it's there and we can't rule out that Josephus lost track of the actual chronology. Couple that with his "seventy years" refers just two paragraphs before that seems to contradict the fifty year reference and it all makes sense. This is Josephus' own cryptic way of trying to explain in relation to the rule of Nabonidus and the 20-year rule of Cyrus when Babylon fell and when Darius the Mede came to the throne; Babylon fell in the 13th year after year 7 of Nabonidus and Darius the Mede became king for 6 years in the 14th year after the 7th of Nabonidus.
Because Cyrus became king twice, once in Pesia and later in Babylon, Josephus can play on that and contradict himself with the "fifty years" for those who don't know. But since the 50 years works with Cyrus first becoming king in Persia after fifty years but also works when he became king in Babylon at 70 years, Josephus cannot be said to be contradicting himself, simply playing around with the historical references. Jewish readers would be further tipped off as well since they know that the temple was finished in the "sixth" year of Darius I and not the second. Josephus plays these "number games" elsewhere in his writings if you want another example.
But regardless of the above "coincidence", no one can legitimately claim Josephus changed his mind after research discoveries and corrected the seventy years to fifty in his last work. That is simply erroneous and uninformed since in the same work he mentions the fifty years, he also reiterates the seventy years again. Hardly a mind change unless he got an epiphany between paragraph 19 and 21 and wanted us to share the epiphany by not changing the 70-year reference, publishing it along with the 50-year reference in his last work! Hardly! Josephus knew the chronology had been revised and he was playing both sides of the fence. His way of providing the history of Babylon and it's fall during the 20-year rule of Cyrus was to substitute Tyre for Babylon. Josephus knew the original chronology and this was his way of perserving the history without making a more obvious contradiction.
By the way, if you want a complete revision, it would be for the reign of Evil-Merodach which he claims (and correctly so) in Antiquities that he ruled for 18 years, but in "Against Apion" only 2 years, the number in the popular chronology.
Basically, the NB Period is 26 years shorter than assigned by the Bible. The reductions are 2 years from Nebuchadnezzar (45 vs 43), 16 years from Evil-Merodach, who ruled 18 now 2, 2 years from Nabonidus who ruled 19 now 17, and the entire 6-year rule of Darius the Mede reduced to zero in the revised chronology. Joephus gets it right that Evil-Merodach ruled for 18 years in "Antiquities" but claims only 2 years in "Against Apion." Too bad he didn't do that with the "seevnty years" reference. Josephus' reflection of the "seventy years" and when they began is precisely as the Bible likewise indicates.
JC