I had always thought that they were Chaldeans, who had the prophecies of Daniel, and were able to calculate the exact date from the Decree of Cyrus, the Mede.
But I have no idea if that was provable.
Thanks TC.
see post #12
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Biblical Predictions As To The Time Of Messiahs (Jesus) Coming...........
4.Messiah must come 483 years after a specific date in Daniels time. This definite prediction as to the exact time of the coming of Messiah is one of the most wonderful prophecies in the entire Bible. It establishes the date of Messiahs advent almost 500 years before He came. Here is the prediction:
Know therefore and understand, that from the going forth of the commandment to restore and to build Jerusalem unto Messiah the Prince shall be seven weeks, and threescore and two weeks; the streets shall be built again, and the wall, even in troublous times. And after threescore and two weeks shall Messiah be cut off, but not for Himself; and the people of the prince that shall come shall destroy the city and the sanctuary Dan. 9:25, 26.
The date of the commandment to restore and to build Jerusalem was the decree by Artaxerxes in 444 B.C., granting permission to the Jews to return to Palestine and rebuild the city of Jerusalem (see Neh. 2:1-8).
The Hebrew word translated weeks in the Scripture quoted above (Dan. 9:25, 26) means sevens or heptads, and is used for years. (See Lev. 25:8; Gen. 29:27-28). In other words, the seventy sevens that are prophetically determined on Israel and on the holy city, with specific events (vs. 24), is a period of 490 years. This period is divided into 3 sections: (1) Seven weeks, or seven sevens of years the 49 years the prophet allotted for the rebuilding of Jerusalem under the leadership of Nehemiah and Ezra and those associated with them. History tells us it took 49 years to do this rebuilding job; (2) A second period of 62 weeks, or 434 years, which would bring the time to Messiah; (3) The 70th week, a period of seven years some time after the coming of Messiah.
We now are especially interested in the period from the commandment to restore and to build Jerusalem to Messiah the Prince, which totals to a period of 483 years. Sir Robert Anderson in his book, The Coming Prince, figured it out, and gave the world his findings. We quote from the facts he presents:
He starts with March 14, 444 B.C., the date of the commandment to restore and build Jerusalem (some authorities differ as to the exact date, the dates given ranging from 454 to 444 B.C., within a ten-year period. In any event, the 483 years that begin with this event bring us to the time of Jesus); and he ends the period with Jesus triumphal entry into Jerusalem (which he believes was the official presentation of Messiah as Prince to Israel. Cf. Lk. 19:38-40 with Zech. 9:9). After careful investigation and consultation with noted astronomers, he gives these startling findings: From 444 B.C. to 32 A.D. is 476 years; 476 x 365 is 173, 740 days; from March 14 to April 6 (the day of Christs triumphal entry) is 24 days; add 116 days for leap years, and you get a total of 173, 880 days. Since the prophetic year of the Bible is always 360 days, the 69 sevens of this prophecy in Daniel (69 x 7 x 360) is 173, 880 days! And so, the time given by Daniel from the commandment to restore and build Jerusalem to Messiah the Prince comes out perfectly to the very day!
This is a genuine prophecy, as detailed as a road map, with no taint of ambiguity; and it is a prediction that can be proven true. It is a sign that points unerringly to Jesus of Nazareth who was Messiah the Prince, who was cut off (by a violent death) but not for Himself. When Jesus began His public ministry, He said significantly, The time is fulfilled and the kingdom of God is at hand Mark 1:15. Messiah must be born at some time; it might have been in any century, in any year; but with absolute certainty the exact year, the very month of a notable event in His life, is foretold.
It is most remarkable that within a generation of Christs sufferings on the cross the temple was destroyed, the Jewish priesthood ceased to exist, the sacrifices were no longer offered, the Jews genealogical records were destroyed, their city was destroyed, and the people of Israel were driven out of their land, sold into slavery, and dispersed to the four corners of the earth! Since those dreadful national judgments fell on Israel, it has been utterly impossible for a Messiah to come with proper credentials, such as the Old Testament demands, and such as Jesus of Nazareth presented.
(The above information was taken from Fred Meldaus Messiah in Both Testaments, pages 29-35).
http://www.campuschristians.info/articles/biblicalpredictions.html