In his memoirs, Nehemiah states that his intercessory prayer for the Jewish people took place in the month of Kislev in the twentieth year of the king (Neh. 1:1). Kislev is the Jewish name for one of the months on the Babylonian calendar, employed during the fifth century BC by both the Jews and the Persians (1).
Here is where a knotty problem arises. In the days of Artaxerxes, the Persian month equivalent to Nisan on the Jewish calendar was the beginning of the regnal year; that is, the beginning of the next year in the numbered years of a king’s reign. If a king ascended the throne in any other month, his first year did not start until the following Nisan, and the remaining time until Nisan was called his accession year. Thus, the first Nisan during his reign marked the beginning of his first year, the second Nisan the beginning of his second year, and so on.
The date of Nehemiah’s prayer appears inconsistent with the date given for his later interview with the king. Although the stated month is Nisan, the stated regnal year is still the twentieth (Neh. 2:5). If the first date is year 20, the second should be year 21. But what looks like a difficulty evaporates when the matter is probed more deeply with the aid of some reasonable assumptions.
1. The dates in Nehemiah 1 and 2 are free of thoughtless error. The first assumption accords well with who Nehemiah was. As a high official in the Persian court, he certainly knew when events took place in relation to the king’s official regnal years. Since the dates in his memoirs do not agree with standard Persian reckoning, the most reasonable explanation is that he chose not to use it. Instead, he computed the king’s regnal years from a starting point other than Nisan.
Siegfried H. Horn and Lynn H. Wood point out that if Nehemiah’s dates did not follow an accepted calendar, the error would have been transparent to early readers and would not have been passed on faithfully without correction (2). Yet we find no correction either in any Hebrew text or in the Septuagint (the Greek Old Testament translated in perhaps the third and second centuries BC). It is well known that the translators of the Septuagint did not hesitate to change the Hebrew text wherever they thought (incorrectly) that it could be improved (3). Evidently, early readers understood that Nehemiah was using a valid form of reckoning.
1. In the kingdom of Judah, the first month of the regnal year was Tishri. Tishri was the month of the autumnal equinox, whereas Nisan was the month of the vernal equinox. From ancient times, the Israelites had regarded the older equivalent of Nisan (Abib) as the beginning of the religious year (Exod. 12:2; 13:4) and the older equivalent of Tishri (Ethanim) as the beginning of the agricultural (4) or civil year (5). Still today, Tishri is the month of the Jewish New Year. Several converging lines of evidence suggest that Tishri was also the beginning of the regnal year in the kingdom of Judah, at least in its closing days (6).
To demonstrate that Judah’s regnal year during this period did not begin in Nisan, Edwin R. Thiele points to the dates in the Biblical account of the reforms initiated by King Josiah, a king of Judah whose reign ended a few decades before the fall of Jerusalem (7). In 2 Kings 22:3, the opening event leading to these reforms—the king’s dispatch of his emissary Shaphan to see Hilkiah the high priest—is placed in the king’s eighteenth year. During his interview with Hilkiah, Shaphan learned that the priests had recently discovered the book of the law. Subsequently, in compliance with the law, the king led the nation in the celebration of Passover. In 2 Kings 23:23, this Passover is placed in the king’s eighteenth year also. Obviously, since preparations for the festival were elaborate, the eighteenth year could not have started on Nisan 1, just two weeks before the start of the festival on Nisan 14 (8).
Further evidence that Tishri-to-Tishri reckoning was actually employed by the Jews in the period before 586 BC is provided by the Book of Daniel. In Daniel 1:1 it is stated that Nebuchadnezzar besieged (or threatened siege to (9)) Jerusalem in Jehoiakim’s third year. Jehoiakim had come to the throne in the autumn of 609 (10). The Babylonian Chronicle records that in 605, Nebuchadnezzar routed the Egyptian army at Carchemish in northeastern Syria (11) and swept southward to conquer all the region about Hamath in west-central Syria (12). In reference to the same events, Josephus says that Nebuchadnezzar “occupied all Syria, with the exception of Judaea, as far as Pelusium [on the Egyptian border]” (13). Then, after hearing of his father’s death on Ab 8 (August 16 (14); Ab is before Tishri), Nebuchadnezzar rushed back to Babylon to claim the throne (15). Berosus, a Babylonian priest who died about 250 BC, states in his history of Babylon that Nebuchadnezzar had Jewish captives in his possession before he returned home for his coronation (16). Thus, the incident in Daniel 1:1 must have occurred in the late spring or the summer of 605.
Notice that the incident could not be dated in Jehoiakim’s third year if Daniel was computing regnal years from Nisan to Nisan. Then it was his fourth year by accession year dating and his fifth year by nonaccession year dating. It was his third year only if Jehoiakim ascended the throne after Tishri 1, 609, and Tishri-to-Tishri accession year dating was the basis of his regnal years. In that case, his first year began in Tishri 608 and his third year began in Tishri 606; thus, the siege of Jerusalem fell in his third year (17).
3. The settlement founded in Jerusalem by returning exiles continued to regard Tishri as the first month of a king’s regnal year. During this period, the people of Judah enjoyed considerable autonomy (18). The Persians allowed them to strike their own coins (19) and granted broad civil as well as religious authority to their priests (20). For a while, as an expression of anti-Persian nationalism, the Jews in their everyday speech abandoned Aramaic, the predominant language of the empire, and reverted to Hebrew (21). It would not be surprising if concurrently they also returned to a traditional calendar.
4. If Nehemiah is not using Persian reckoning, he must be using Jewish reckoning. Internal evidence (Neh. 13:6–7, for instance) suggests that the book was written in Jerusalem. Moreover, his choice of language (Hebrew), his careful recording of facts that he did not need to record for himself, and the actual survival of his book—all indicate that his purpose was to set down a history that would be read by Jewish posterity. Therefore, he computed the dates at the outset of his memoirs in terms of a regnal year beginning in Tishri (22). Many scholars have endorsed this conclusion (23).