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How old is the world 1) from the creation of the first day and then 2) from the creation of Adam?

If Adam and then each of his descendents lived for around 1000 years, and then Noach and his descendents, and then Avraham and his descendents, then isn't this world older than we think it is?

marked as duplicate by Yaacov Deane, Gershon Gold, Isaac Moses, Shmuel Brin, Daniel Jan 23 '17 at 20:10



1) Great question. There are opinions that it was 7 actual 24 hour days before the creation of Adam. There are opinions that the 7 days were epochs of time that were undefined. I have even seen an opinion by professor Gerald Schroeder (his book Genesis and the Big Bang and the rest of that series), that it was both 24 hour days AND epochs of billions of years at the same time.

2) From Adam it would be 5777 years ago. That is the date used by the Jewish calendar.

  • Thank you for answering my question but 5777 still doesn't make sense to me. Moshe gave exact numbers of years in Bereishit. Add them up, with overlaps, and and you will see how we have under-calculated the years. – devorah Dec 18 '16 at 10:13
  • 2
    You are welcome Devorah. It would seem that the burden is upon you to state a claim. How many years by your reckoning does Moses write for us in the Torah if it isn't 5777. Please provide a short proof/calculation with your number. Thanks. :) – David Kenner Dec 18 '16 at 10:21
  • And thank YOU, David. Next time I get free time between work, I sure will...armed with calculator, pen and paper. – devorah Dec 18 '16 at 11:06
  • I'm looking forward. :) – David Kenner Dec 18 '16 at 11:09
  • Note Seder Olam isn't the only opinion out there, even if it is the convention used on contracts. More like 5777 +/- 400 – Double AA Dec 18 '16 at 15:38


I already have the calculations done for you in my blog. Rabbi Liebtag gave shiurim based on the Seder Olam and Rabbi Breuer's discussion of the time between the destruction of the first temple and the building of the second temple. Note that this explains why we use 5777 for this year. Any time before Adam is considered not relevant. It does not matter whether is was six days or six "time periods". The count of time did not start until after the creation of Adam.

The geneologies used are based on the number of years given from the birth of each person until the birth of his son. Thus we have a table like this.

 Name     Father’s age at time of birth   Year of birth

Adam                   N/A                      0
Sheit                  130                    130
Enosh                  105                    235
Keinan                  90                    325
Mahalaleil              70                    395
Yered                   65                    460
Chanoch                162                    622
Metushelach             65                    687
Lemech                 187                    874
Noach                  182                   1056

And Noach was 600 years in 1656 when the flood came.

  • @devorah Here is the calculation showing how the years were determined. – sabbahillel Jan 18 '17 at 20:43

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