Note 066
The safest aeras of Abulfeda, (in Vit. c. i. p. 2,) of Alexander, or the Greeks, 882, of Bocht Naser, or Nabonassar, 1316, equally lead us to the year 569. The old Arabian calendar is too dark and uncertain to support the Benedictines, (Art. de Verifer les Dates, p. 15,) who, from the day of the month and week, deduce a new mode of calculation, and remove the birth of Mahomet to the year of Christ 570, the 10th of November. Yet this date would agree with the year 882 of the Greeks, which is assigned by Elmacin (Hist. Saracen. p. 5) and Abulpharagius, (Dynast. p. 101, and Errata, Pocock's version.) While we refine our chronology, it is possible that the illiterate prophet was ignorant of his own age.
Note: The date of the birth of Mahomet is not yet fixed with precision. It is only known from Oriental authors that he was born on a Monday, the 10th Reby 1st, the third month of the Mahometan year; the year 40 or 42 of Chosroes Nushirvan, king of Persia; the year 881 of the Seleucidan aera; the year 1316 of the aera of Nabonassar. This leaves the point undecided between the years 569, 570, 571, of J. C. See the Memoir of M. Silv. de Sacy, on divers events in the history of the Arabs before Mahomet, Mem. Acad. des Loscript. vol. xlvii. p. 527, 531. St. Martin, vol. xi. p. 59. - M.
Dr. Weil decides on A.D. 571. Mahomet died in 632, aged 63; but the Arabs reckoned his life by lunar years, which reduces his life nearly to 61 (p. 21.) - M. 1845]
The History Of The Decline And Fall Of The Roman Empire Fall In The EastChapter 50