Sure, but I'm working within the confines of the OP's mythos. Presumably, the current sabbatical cycle began with Creation Week, which presumably lasted 7000 years (unless "1 day = 1000 years" is only meant to be applied when convenient). Since Adam was created during Creation Week, there would need to be an additional ~2.5 billion years after Adam's creation before the Destruction happens, which means ~2.5 billion years of human history.
That timespan for human history is not attested in either the geological record or the biblical record. In order for this numerology stuff to work out, either (1) we've got a long time to go before Destruction, or (2) there is some unattested "human history" somewhere; e.g., Adam and Eve lived alone in the Garden of Eden for billions of years before the Fall, or Adam's and Noah's biblical ages were given in divine years (so Adam died at age 339,682,500), or something like that.
This very issue was addressed by Rabbi Aryeh Kaplan, who as far as I can tell is the origin of the claim that Isaac of Akko accurately dated the universe. The appeal is to the two accounts of creation in Genesis. The seven days happened
before the Big Bang, and referred to the creation of the world and man in thought, whereas the second account refers to the deed. So the seven days, be they God days or human days, are not part of the 15 billion years and man was, indeed, created a few thousand years ago.
Based on the quotes of Isaac given by Kaplan, he does not appear to have actually done the calculation of 15 billion years, but he did argue the world was very old if this is an accurate translation:
quote:
I, the insignificant Isaac of Akko, have seen fit to record a great mystery that should be kept very well hidden. One of God’s days is one thousand years, as it is written, For a thousand days in Your sight are as a day (Psalms 90:4). Since one of our years is 365¼ days, a year on high is 365,250 of our years. Two years on high is 730,000 of our years. From this, continue multiplying to 49,000 years, each year consisting of 365¼ days, and each supernal day being one thousand of our years, as it is written, God alone will prevail on that day (Isaiah 2:11). Who can speak of God’s greatness? (Psalms 106:2). Blessed be the name of Him whose glorious Kingdom is forever and ever.
All this relates to what the Scripture states. However, no matter how many times this picture is doubled, even thousands upon thousands, it would not even be like a second to [God]... However, with regard to the Infinite One, it is enough that He is called Infinite.
and more explicitly:
quote:
Behold, our eyes see that the world has existed for a very long time. This is to refute the opinion of those who say that the world has not existed more than forty-nine thousand years, which is seven Sabbatical cycles.
Edited by caffeine, : No reason given.
™ Version 4.2