Q. This past Sunday I explained to the SS Class the difference between Life Span and Generation Span. One question which I had no answer for was, if the Bible, I think in Psalm, states we have 70 years, or if lucky, 80 years, does it state in the Bible why after the Flood, if people like Abraham, Isaac, etc, lived into their 100’s…why did the age fall from that span back to the 70 or 80 range?
A. Life spans had approached nearly 1000 years before the flood, but afterward became progressively shorter until they stabilized at 70 years, as indicated by Psalm 90:10. Some believe this is partially due to the water vapor shield that originally surrounded the Earth (Gen. 1:6-8) but collapsed at the time of the flood in order to provide some of the water necessary. They say this canopy deflected harmful rays from outer space that have a life shortening effect. As an example, Noah’s son Shem outlived 8 of the first nine 9 post flood generations, including Abraham’s. Today the Earth’s electromagnetic field performs a similar function, though not as well.
Isaiah 65:20 hints of the return of long life spans to Earth during the Millennium. Perhaps during the Earth’s restoration at the time of the 2nd Coming (Matt. 19:28) this water vapor canopy will be restored.