This argument would be correct as far as the former (Aaron's) case is concerned, for the text specifically mentions (forty years after) the Exodus but in the latter (Moses') case, how can we tell that (the fortieth year) means from the Exodus? Perhaps it means (the fortieth year) from the raising of the Tabernacle in the wilderness. Since he mentions the fifth month, which is certainly Abh, and he speaks of (Aaron's death as happening in) the fortieth year (and not the forty-first year), it is clear that Tishri is not the beginning of years (for kings). This would be improper, for it is written : 'And Aaron, the Priest, went up into Mount Hor at the commandment of the Lord, and died there, in the fortieth year after the children of Israel were come out of the land of Egypt, on the first day of the fifth month.' And it is written : 'And it came to pass in the fortieth year, in the eleventh month, on the first day of the month, Moses spake,' etc. But how do we know that the Exodus even should be reckoned from Nissan? Perhaps we should reckon it from Tishri. So also is the reign of Solomon reckoned from Nissan. Johanan says: Whence do we deduce that we reckon the commencement of years (for the reign) of kings, only from Nissan? Because it is written : 'And it came to pass in the four hundred and eightieth year after the going forth of the children of Israel out of the land of Egypt, in the fourth year of the month Ziv, which is the second month of the reign of Solomon over Israel.' Thus the Scriptures establish an analogy between 'the reign of Solomon' and 'the Exodus from Egypt.' As the Exodus from Egypt is reckoned from Nissan, He comes to teach us that such is not the case. 1 Is this not self-evident? The case here mentioned refers to an instance where the new king was a son of the deceased, and, while ascending the throne in Nissan, had been elected in the month of Adar, and being the king's son, it might be assumed that he was king immediately after his election, and thus the following first of Nissan would inaugurate the second year of his reign. But if a king die in Adar, and his successor does not ascend the throne until Nissan, then the year ending with Adar should be referred to as the year of the dead king, and from Nissan it should be referred to as that of his successor. If a king die in Nissan, and his successor ascend the throne in Nissan, the same is the case. The rabbis taught: If a king die in Adar, and his successor ascend the throne in Adar, (documents may be dated either) the (last) year of the (dead) king or the (first) year of the new king. The Boraitha teaches this lest one say that the year should be reckoned from the day of election, and therefore the king would begin his second year (on the first of Nissan following). From this we infer, that only Nissan is the commencement of years for kings (or the civil New Year) that even a fraction of a year is considered a year and that if a king ascends the throne on the first of Nissan, he is not considered to have reigned one year until the next first of Nissan, although he may have been elected in Adar. The rabbis taught: A king who ascends the throne on the 29th of Adar must be considered to have reigned one year as soon as the first of Nissan comes, but if he ascends the throne on the first of Nissan he is not considered to have reigned one year until the first of Nissan of the following year.

The year of the king's reign mentioned in the documents. Hisda: 'On account of documents.' So that in the case of mortgages, one may know which is the first and which is the second by means of GEMARA: 'For kings.' Why is it necessary to appoint such a day? (Let every king count the day of his ascension to the throne as the beginning of his year.) Said R. 5 On the first day of Shebhat is the New Year for trees, 6 according to the school of Shammai but the school of Hillel says it is on the fifteenth of the same month. The first of Tishri is New Year's day, for ordinary years, and for sabbatic years 3 and jubilees and also for the planting of trees 4 and for herbs.

MISHNA I.: There are four New Year days, viz.: The first of Nissan is New Year for (the ascension of) Kings and for (the regular rotation of) festivals 1 the first of Elul is New Year for the cattle-tithe, 2 but according to R. THE ORDINANCES ABOUT THE NEW YEARS OF THE JEWISH CALENDAR-THE MESSENGERS THAT WERE SENT OUT FROM JERUSALEM-AND AT WHICH PERIOD OF THE YEAR THE WORLD IS DIVINELY JUDGED.

1553970 Talmud (Rodkinson Edition) - Book 2: Tract Rosh Hashana, Chapter I

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