Question: Somewhere, though I don’t remember where, I have heard that it had never rained on the earth when Noah built the ark. That prior to the flood everything had been watered from within the earth. Is this biblically true or just something that someone came up with?
Answer: The Bible doesn’t say definitively, but there is a theory among some more scientific Christians that when it says in Genesis 1 that God separated the water under the expanse from the water above it (1:7) that this was the formation of a water canopy above our atmosphere. Its properties would have served to create a greenhouse affect around the earth so that it would be evenly warm all over our globe. It would have filtered out harmful ultraviolet rays that do damage to organisms. In this view, the canopy also created a much different kind of air pressure that would allow for Pterodactyls to fly and reptiles to grow to enormous sizes, hence the dinosaurs. And it would have possibly prevented rain.
On this theory, when Noah was told that it was going to rain and announced the same to his contemporaries, they had never seen or heard of this kind of precipitation. Noah’s faith is perhaps even greater than we thought.
Genesis 2:5,6, says, “Now no shrub had yet appeared on the earth and no plant had yet sprung up, for the LORD God had not sent rain on the earth and there was no one to work the ground, but streams came up from the earth and watered the whole surface of the ground.” This could suggest that soon thereafter, when shrubs did appear on the earth, God began to send rain. In this case, rain was not new to Noah or any other of earth’s inhabitants, but it would have been difficult to believe that God was going to destroy all of earth’s inhabitants by a flood.