|Photo by Justin Vidamo|
We read in the Bible of people living 900 years or more before the flood. After the flood, the average lifespan slowly decreased, from 450, to 250, and at last to 80. Why?
First of all, it wasn't because of God's words in Genesis 6:3; “his days shall be 120 years.” That verse was actually speaking of the allowance of time God had given man in which to repent before the flood came to destroy them. But if it wasn't that, what was it?
Some people have suggested it was a change in diet. Before the flood, meat eating was not allowed. However vegetarians today live no longer than other folks, so we know that can't be true.
What about environmental changes? Some hypothesize that the pre-flood world could have been very different in terms of atmospheric pressure and oxygen levels, but neither of these is likely to have been the culprit. Noah stepped off the ark at 600 years old, and yet the post-flood environment had no negative effect on the rest of his life. In fact, he lived to become the third oldest person in human history!
The most likely cause for shorter life-spans after the flood is genetics. Shem only lived to be 600 (we don't know how long Ham and Japheth lived), despite having been born in the same environment as Noah, and whatever it was that caused his “early” aging was passed down to his descendants, none of whom lived longer than he did.
Lamech, Noah's father, only lived to be 777, which was quite young. He could have well passed down the genetic marker for premature aging to his grandsons, and with the bottleneck of the flood, there would have been no infusion of fresh DNA in the post-flood bloodline to prevent all of Noah's decedents from being affected. One little mutation, and we lost 300 years. The dispersion at the Tower of Babel provided yet another bottleneck, paring down the pool of genetic information available to each people group—and mutations multiplied, and with them, apparently, came yet another drop in the average lifespan.
I know, I know. That wasn't really a short answer. But I tried!
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