Total years from Creation to Abraham
Alexandrian: 3463
Masoretic: 2107
Difference: 1356 years
Abraham was born in 2322 B.C. Adding this to the Alexandrian age gives 5785 years from Creation to Christ. Adding to the Masoretic, however, only gives 4429 years from Creation to Christ. One of the reasons for the discrepancies between the Alexandrian as we have given it and the age as figured by most of the above listed church fathers is that Terah is listed as 70 when his first son was born, but that was evidently not Abraham, for Abraham was about 75 when his father died at 205 years old (Genesis 11:32, Genesis 12:4), and that would make Terah, as we show above, about 130 when Abraham was born. This does not answer for the full discrepancy, but it does narrow the gap a bit.
"Why, then, are our modern Bibles today giving us an age of about 6000 years since Creation for our time? The answer lies in the Masoretic text, from which all our modern Bibles, including the modern Hebrew, have arisen. The Masoretic is a product of the Council of Jamnia, a series of 'discussion groups' which met about 100 A.D. The Romans has destroyed the Temple in Jerusalem in 70 A.D., and thus also destroyed the original manuscripts of the Scriptures. Copies, of course, remained, primarily known today as the
Alexandrian Septuagint (LXX) and the Samaritan Pentateuch. The rabbis, gathered under Rabbi Akiba, wanted to formulate a new 'official' copy of the Hebrew Scriptures. In doing so, they switched from the more ancient paleo Hebrew (sort of like our cursive) to the modern block Hebrew characters. (They also left out the vowel points, which were not restored until 900 A.D., and then on the basis of oral tradition.) Because they wanted to eliminate the ability of the new Christian sect to use the Hebrew scriptures as evidence that Jesus of Nazareth was the Messiah, they altered some of the quotes used by the Christians which came from the Old Testament. This is why many of the quotes used in today's Bibles do not match the referents in the Old Testament. In at least one case (Hebrews 1:6), the referent, Deuteronomy 32:43, is so changed as to be unrecognizable. It is there, however, in the Alexandrian. In addition, the rabbis in the Council felt that the genealogies in Genesis must be wrong. It would be dishonoring to God for a man to wait until after he was a hundred or a hundred and fifty to have a son. So, in many cases, they simply dropped the cipher for "100" from the ages of many of the men at the time their mentioned son was born. This effectively chops over 1300 years off the age of the earth in terms of the Masoretic texts."