When was Abraham alive?

I, along with others, have done studies on the chronology of the Old Testament genealogies - which puts Abraham being born ~1950 years after Adam, and about 300 years after the flood.

Given that the earth is approximately 6000 years old, that makes Abraham's birth about 2050BC.

Dating biblical events from Creation and/or from the Christian Era depends on the positions adopted on two disputed points:

1. The birth of Abraham. There are two positions on the age at which Terah begot Abraham:

• Early birth: Terah was 70 y.o. at Abraham's birth and therefore 145 y.o. at Abraham's departure from Haran.

• Late birth: Terah was 130 y.o. at Abraham's birth and died being 205 y.o. before Abraham's departure from Haran.

The position on this point affects the date from Creation of biblical events from Abraham's birth forward, and the date from the Christian Era of biblical events previous to Abraham's birth.

2. The sojourn in Egypt. There are two positions on the time elapsed between Jacob's entry into Egypt and the Exodus:

• Short sojourn: 215 years.

• Long sojourn: 430 years.

The position on this point affects the date from Creation of biblical events following Jacob's entry into Egypt, and the date from the Christian Era of biblical events previous to the Exodus.

Thus, each of the 4 possible combinations of the positions on these disputed points can give a different date for a biblical event, either from Creation, or from the Christian Era, or from both.

In the particular case of Abraham's birth:

• the date from Creation (AM, Anno Mundi) depends on the position on his birth; and

• the date from the Christian Era (BC, Before Christ) depends on the position on the sojourn in Egypt.

IMHO, a good source for an introduction to the two disputed points and links to further bibliography is:

https://creationwiki.org/Biblical_chronology_dispute

From that source I made the following table with the year of Abraham's birth in the format (AM, BC) for each combination of the positions on the disputed points, adding 1 to the BC dates in Thiele's chronologies because in each system the sum of the AM and BC dates of any event, including Creation, must be constant:

            | short sojourn | long sojourn |
------------+---------------+--------------+
Early birth | (1948, 1952)  | (1948, 2167) |
------------+---------------+--------------+
Late birth  | (2008, 1952)  | (2008, 2167) |
------------+-------------- +--------------+

Note on the short sojourn position

The short sojourn position fits a literal reading of Moses' genealogy from Levi (Ex 6:16-20), noting that Levi's son Kohath had already been born when Jacob entered Egypt (Gen 46:11). Denoting Kohath's age at the entry into Egypt as K_E, Kohath's fathering age (i.e. his age at Amram's birth) as K_FA and Amram's fathering age as A_FA, and since Moses was 80 y.o. at the time of Exodus (Ex 7:7), we have:

Exodus - Entry into Egypt = K_FA - K_E + A_FA + 80

where Kohath's and Amram's begetting ages must be less than their respective lifetimes and K_E must be greater than zero. Thus, a sojourn time of 215 years can be achieved in a number of ways, such as setting the fathering ages at the middle of the respective lifetimes:

For K_E = 1, K_FA = 67 & A_FA = 69, sojourn time = 215 years

This is fully compatible with Num 3:27-28 stating that the number of male descendants of Kohath was 8600, as e.g. in this way:

Years - Age --- Age ----- Age -- Age -- Kohath's
from -- of ---- of ------ of --- of --- patrilineal
entry - Kohath  Jochebed  Amram  Moses  male descendants
  0 ---   1 ---  .. ----  .. --- .. --- .
 30 ---  31 ---  .. ----  .. --- .. --- 4
 60 ---  61 ---  15 ----  .. --- .. --- 4 x 4 = 16
 90 ---  91 ---  45 ----  24 --- .. --- 16 x 4 = 64
120 --- 121 ---  75 ----  54 --- .. --- 64 x 4 = 256
150 --- xxx --- 105 ----  84 --- 15 --- 256 x 4 = 1024
180 --- xxx --- xxx ---- 114 --- 45 --- 1024 x 4 = 4096
210 --- xxx --- xxx ---- xxx --- 75 --- 4096 x 2 = 8192

According to the Bible, Abraham was born 2166 BC, and died 1991 BC, starting from well-established dates.

The reign of King Solomon began 971 BC. (See "Mysterious numbers of the Hebrew Kings" by Edwin Thiele.)

(You could also use 587 BC for destruction of Jerusalem by Babylonians, and the year of Ezekiel 40:1 (14th after destruction of city), together with Leviticus 25:9-10, and the Seder Olam's information that the Jubilee Year in Ezekiel 40:1 was the 17th Jubilee (with Jubilees happening every 49 years, plus 40 years in the wilderness, to get 1446 BC for the year of the Exodus. See answer to "When was David born?" for an explanation of this route.)

1 Kings 6:1 :- 971 BC - 4 = 967 BC, Solomon’s Temple began to be built

1 Kings 6:1 :- 967 + 479 = 1446 BC, Exodus

Exodus 12:40,41 :- 1446 BC + 430 = 1876 BC, Jacob enters Egypt at Passover after two failed harvests, before the third failed harvest, early 3rd year of famine in days of Joseph.

Genesis 47:9 :- 1876 BC + 130 = 2006 BC, Jacob born

Genesis 25:26 :- 2006 + 60 = 2066 BC, Isaac born

Genesis 21:5 :- 2066 + 100 = 2166 BC Abraham born

Genesis 25:7 :- 2166 – 175 = 1991 BC Abraham went to glory.

So Abraham was born 2166 BC, and died 1991 BC.

Answering this question over 10 years after it was posted gives both an advantage and a disadvantage. The disadvantage is that the preferred answer has been chosen, which my answer disagrees with. The advantage is that the various arguments and calculations can be compared and that it is worth-while posting another one which agrees with the 2166 to 1991 B.C. era answers, as it presents a slightly different route.

This route is the "working backwards" one (which is something I am strangely prone to do a lot, myself). I quote now from the booklet below, re. how to find a starting point in developing a biblical chronology:

"One of the problems faced in this pursuit is that the biblical chronological data is all relative rather than fixed. In other words reference points are taken from elsewhere in the historical narrative. This means that, in order to make a start, you have to identify a fixed, objective and external time reference from which to calculate all other dates. There are in fact two such fixed, external points that we can work from.

1 - 586 BC - It would appear that there is virtually universal agreement, both among biblical and non-biblical scholars, that the fall and destruction of Jerusalem occurred in 586 BC.

2 - 931 BC - Again, there is widespread, though certainly not universal, agreement that the division of the kingdom following the death of Solomon happened in 931 BC.

...Starting from these fixed reference points and working backwards, it is possible to determine with a real degree of certainty, other dates in biblical history, alll the way back to Abraham...

• the kingdom was divided in 931 BC, after Solomon's death

• since Solomon reigned for 40 years (1 Kings 11:42), he must have become king about 971 BC

• Solomon began building the temple during his fourth year as king (1 Kings 6:1), i.e. c.966/7 BC

• at the time of the Exodus, Israel had been in Egypt for 430 years (Exodus 12:40), so Jacob must have gone to Egypt in 1876 BC

• Jacob states that he was 130 years old when he appeared before Pharaoh (Genesis 47:9), so his birth can be dated at about 2006 BC

• Isaac was 60 when Jacob was born (Genesis 25:26), so his birth would have been about 2066 BC

• Isaac was born when Abraham was 100 (Genesis 21:5), so Abraham must have been born in 2166 BC." A Concise Chronology of the Bible, p10, John D Brand, Edinburgh Bible College 2014