This is my opinion:
When the watchers came down from heaven and mated with the women of the earth, they created offspring which were called the Nephilim. These nephilim
were bloodthirsty giants and sought to wreak havok on mankind. Mankind could not sustain them.
Also, when the watchers came down they started teaching humans all sorts of things we were not supposed to know. Their "knowledge" corrupted us. So
in the bible we can see that knowledge of secret teachings is not good for us. It's just not our purpose in life. It's the same lesson that's told
with Adam and Eve. Perfect humans are essentially ignorant humans. Once you are on that path to secret knowledge, you are on a road of ultimate
corruption.
The reason Noah and his family were chosen by GOD to be saved is because they were the only family who had not been corrupted. Their DNA was still
purely human, not the human-angelic hybrid. Noah lived well into his 900's as well. So a lengthy life is not an alteration of our being, but a trait
originally given to us by the Lord.
So the flood was meant to
A: get rid of the nephilim who were destroying the world anyway (sinning against all animals and creatures)
B. stop the secret practices that humans were taught by the watchers and were practicing in a big way (everything from astrology to warfare and
inbetween - most of which are still being practiced to this day)
C. lessen the life span of the corrupted humans because of our sinful ways
C is probably more of a favor to us. If a sinning person were to sin for hundreds of years, think of how long it would take that person to redeem
himself in the eyes of the Lord.
I think it is true that people did live to see very old age in olden days based on a number of reasons. Yes they were probably healthier, yes they
were much more pious, yes they had a more direct contact with their creator, yes they were probably of a larger stature than we are now, basically
they just were more perfect specimens of humans than we are today.
Also, I do think there was probably a water canopy surrounding the earth before the flood. Think about an unborn baby within it's mother's womb. I
think that is a pretty big indicator that we are essentially created and thrive in water, oxygenated water.
It could be that there was a water canopy stopping harmful uv radiation from attacking our skin cells, and it could also be the the atmosphere in
which they lived and breathed may have been composed of oxygen and water.
Actually, there have been scientific research in the field of liquid breathing, as they call it. It has been shown to be very effective in treating
heart patients. You can read more about liquid breathing
here.
Here's a little snippet:
Liquid breathing is a form of respiration in which a normally air-breathing organism breathes an oxygen-rich liquid (such as a perfluorocarbon),
rather than breathing air. In theory, liquid breathing could assist in the treatment of patients with severe pulmonary or cardiac trauma, especially
in pediatric cases. Liquid breathing has also been proposed for use in deep diving[1][2] and space travel.[3] Despite some recent advances in liquid
ventilation, a standard mode of application has not been established yet. Liquid breathing is sometimes called fluid breathing; however, this usage
can be confusing as both liquids and gases are fluid substances.
So what I get from this is that not only is liquid breathing beneficial to us physiologically, it would more than likely preserve us outwardly as
well. If oxygen is what speeds along the decaying process, then it would seem the antediluvian world may have had less of it, leading to a healthier,
better preserved human.
I'm not saying it was a water world, just that the atmosphere that was breathed in may have had a more liquid component to it.
[edit on 15-8-2010 by Privy_Princess]