Tisha B'Av Dates

I received the following question from a Professor here at USC about my previous post:

Dov,Thanks for your Tisha B'Av message.
I am puzzled, however, by the two historical dates that you gave. The destruction date for the First Temple was 586 BCE (the generally agreed year, though some would put it one or two years earlier or later, but no where near your value of423 BCE); and 70 CE for the Second Temple (your 69 CE is close, but Roman dates are not in doubt).
Best wishes,

Attached is my response:

Hi Dr. xxxxx,
It's great to hear from you. I hope all is well.
Re: the dates. I quoted the dates from "The Jewish Timeline Encyclopedia" by Mattis Kantor (published by Aronson).
Although he doesn't list the entire discussion, there are two issues at hand:
a) The date for the Destruction of the Second Temple. This is much more commonly acknowledged as having taken place in 70 CE. There is however a bit of debate within traditional Jewish circles, and some additional reason for confusion:
1) There are two methods of calculating the Jewish calendar. R. Saadiah Gaon and others point out that the calendar dates recorded in the Talmud and in Seder Olam (a historical work from Talmudic times which is the source of much of Jewish historical dating) used the creation of Adam as their starting date. The Jewish calendar as it is universally computed nowadays actually uses the date of creation as year 1, and starts year 2 on the sixth day of creation (Rosh Hashana) with the creation of Adam. That allows for some discrepancies of one year depending on which system is being used, and can translate into the same discrepancies of one year in translation into secular dates as well (69 or 70).
2) There is additionally some dispute as to the exact year of the Destruction of the second temple, depending on whether it was destroyed in its 420th year or after 420 years. Thus, Rashi (avodah zarah 9b) places the Destruction in the year 3828 (68 or 69), while Tosafos contends that it was in the following year (3829 - 69 or 70). Similarly, Maimonides (shemitah v'yovel 10:4) places the destruction in 3829 (presumably 69, but possibly 70).

b) As you noted, the date for the Destruction of the First Temple involves a much greater discrepancy.
Jewish tradition contends that the Second Temple stood for 420 years. In addition, there was a period of 70 years between the Destruction of the First Temple and the building of the Second. A simple count backward of 490 years from the year 3828 would give the date for the First Temple's Destruction as 3338. Translating that to secular date would require subtracting 490 years from 68 CE and then subtracting one more (because there is no year 0 in the secular calendar), which gives us a date of 423 BCE. (Admittedly, for me to have been consistent I should have put either 68 CE for the Second, or 424 BCE for the First).

To explain the discrepancy of some 150 years from the secular dates, I quote from an appendix in the back of Artcroll Publication's "History of the Jewish People: The Second Temple Era":

"These dates are based primarily on the traditional chronology given in Seder Olam, an authoritative work dating back to Talmudic times, and of course on the Talmud itself. Based on Scriptural and Rabbinic source, Seder Olam is founded on an uninterrupted tradition and forms the basis for such halachic determinations as the dating of Shemittah. Secular historians, however, have adopted a sharply divergent chronological system for this period. They date the destruction of the First Temple and the construction of the Second Temple 167 years earlier than does Seder Olam and all other traditional Jewish sources.
Secular history identifies 538 BCE (3223) as the year Cyrus conquered the Babylonian Empire, while our tradition puts this event at 371 BCE (3390). As Scripture states clearly (Ezra 1:1ff and II Chronicles 23:22-3) it was in the first year of Cyrus' reign that the Jewish exiles were permitted to return to Jerusalem. Cyrus' reign began a year after he and Darius the Mede conquered Babylon (see Daniel 9:2 with Rashi, Megillah 12a, and Seder Olam ch. 28-29). 18 years after that the Second Temple was built (see Seder Olam ch. 30, Megillah 11b). Jewish tradition also states frequently and unequivocally that the Second Temple stood for 420 years (see Seder Olam ch. 30, Arachin 12b et al). According to the secular dating of Cyrus' victory, the Second Temple era would have had to be far, far longer than that ascribed to it by every Talmudic source.
Another discrepancy involves the duration of Persian domination of the near East. In the Rabbinic tradition, Persian rule spanned the relatively brief period of 52 years, from 370-318 BCE (3391-3443), 34 of these years being after the construction of the Second Temple. Secular history assigns 208 years to Persia, from 538-330 BCE (3223-3431). According to this latter version, ten Persian kings reigned during those years: Cyrus the Great, Cambyses II, Darius I, Xerxes I, Artaxerxes I, Xerxes II, Darius II, Artaxerxes II, Artaxerxes III, and Darius III. Jewish tradition, however, recognizes no more than four Persians as rulers of the entire known civilized world: Cyrus, Achashvairsoh, Darius, and possibly Cambyses....
This discrepancy has been noted by numerous Jewish scholars throughout the centuries who have insisted that the traditional chronology is incontrovertibly supported by Scripture.
Don Isaac Abarbanel (in his comm.. to Daniel) suggests that some of the Persian kings mentioned in the ancient sources may have ruled Persia prior to its conquest of Babylonia. The Talmudic reference to a 52-year Persian hegemony, however, refers only to the years when Persia ruled the former Babylonian Empire...."

They go on for a while, but that's the gist of it.
Hope this helps. I'd love to hear your comments.
Let me take this opportunity to again extend our invitation to you to join us some time for a Shabbat dinner. I know that our students would gain immensely from an opportunity to interact with you and hear your thoughts.
Dov