In biblical times, people thought that the earth and heaven were all that there was... and that the earth was essentially a 'terrarium' (you might want to look that up). They thought that the sky was a solid object, called the 'firmament', and that the sun, moon, and stars were affixed to it. So, essentially, heaven is 'on the other side of the sky'.
The story of Genesis is comprised of the myths, superstitions, fairy tales and fantastical delusions of an ignorant bunch of Bronze Age fishermen and wandering goat herders, lifted from the oral traditions of other cultures, and crafted into a tale that incorporated some of their own folk tales and pseudo-history. This collection of ignorance provides the basis for the Abrahamic death cults of desert monotheism... Judaism, Christianity and Islam.
The cosmological aspects of Genesis are perfectly understandable, if you contemplate it in the proper context. At the time the bible stories were concocted, the perception was that the earth was the object and the center of creation. Why? Because they had no reason to think otherwise. Today, as we advance science, we stand upon the shoulders of all the scientists that came before. Back then there were no shoulders to stand upon... so they did the best they could with what they had... their senses and their imaginations.
* They had no concept of 'outer space', and so they conceived that in the beginning all that existed were dark waters.
* They had no concept of 'nothingness'. Remember, the concept of 'zero' wasn't invented (discovered?) until thousands of years later. With that in mind, the term 'void', as it is employed in Genesis, can not refer to 'nothingness'... it can only be applied in its alternative definition, which is 'empty'. So, the waters were dark, formless and empty (devoid of content).
* They thought that all of creation consisted of the earth and an unseen 'heaven', and they thought that the sky was a 'thing'... a substantive 'firmament' that was created by god to separate the waters and differentiate earth from heaven, when both were created.
# They had no idea that Earth was a planet, orbiting the sun.
# They had no idea that there is no firmament... that the sky is not a 'thing'.
(If you don't believe that they thought the sky was an object... a solid barrier... consider the Tower of Babel, that they were building to reach heaven. Apparently, God ALSO thought that the sky was an object, since it concerned him so much that he confounded their speech, so as to disrupt their project and keep them from reaching his domain. God must be pretty much of a dumbass, if he doesn't even know the actual configuration of the universe that he created. So much for the 'inerrant' bible.)
* They thought that the sun was a light that god had placed upon the 'firmament' to differentiate night from day.
# They had no idea that the sun is a star... the center of our solar system.
# They had no concept of 'stars' in the same sense that we understand them today.
* They had no idea that night and day were a consequence of the earth's rotation.
* They thought that the moon was a 'lesser' light that god had caused to travel across the firmament to enable man to differentiate the seasons, and provide illumination at night.
# They had no concept of the moon as a satellite.
* They thought that the stars were tiny lights that god had placed upon the firmament to provide for omens. (Some thought that the stars were 'holes' in the firmament that allowed the 'light of heaven' to shine through.)
# They had no idea that the stars were suns, just like our own sun.
# They thought the eyeball-visible planets (Mercury, Mars, Venus, Jupiter, Saturn) were 'wandering stars'.
# They had no idea that the planets were actually sun-orbiting bodies, just like earth.
* They had no idea that the earth, itself, is a planet.
# They had no clue as to the actual nature of the earth, our solar system, the place of our solar system in the galaxy... or even of the existence of our galaxy. (Up until very recently, we didn't even know that there were other galaxies. Our galaxy, when it was first known that there actually WAS a galaxy, was thought to be the whole universe.) From their perspective, the 'earth' and 'heaven' (i.e., whatever existed on the other side of the sky) represented all that there was. A terrarium.
I do not say this things to disparage what they thought back then. They were trying to do what science is trying to do today... trying to understand nature and reality. Today, we have technology and disciplined meta-procedures (scientific method) to help us extract answers from nature.
Back then, they did not.
Today, we have 'theories' to provide a consistent explanatory framework for what we are able to observe in nature, supplemented and validated by the additional information that we are able to extract from nature by means of our technology, our disciplined methods and our intellectual tools (mathematics, logic). Most of our theories are incomplete, so we continue to work on them... because we know that they are incomplete.
Back then, they did not have disciplined methods, and they did not have the technology to extract answers from nature. The only information they had access to was what they could see with their own eyeballs. There was no technological knowledge base or scientific context in which to interpret their observations, so they had to appeal to their imaginations... and the 'supernatural'... in order to make sense out of what they saw. Actually, what they really achieved was deluding themselves into thinking that they knew the truth. Amazingly, over time, this delusion has become codified, institutionalized, and incorporated... complete with franchises.
Basically, Genesis can be thought of as a 'theory', concocted by people who were constrained by lack of technology, methodology and intellectual tools... but they sure weren't constrained by lack of imagination.
Today, we try to interpret Genesis in the context of what we KNOW about the universe... galaxies, stars, planets, moons, gravity, orbits, inclination of the earth's axis, planetary rotation, etc. They problem is that Genesis can't be interpreted in terms of those things, because Genesis was written by men, based on oral traditions, and those men DID NOT KNOW about those things. They could only write about what they could see and what they could guess about the reasons that lay behind what they saw. In any event, it provided them with a mechanism to quell the innate anxiety that comes with fretting about how and why they came to be here.
They guessed wrong.
So... the cosmological aspects of Genesis require a literal interpretation... no metaphors... no allegory... no hidden meaning. The key, though, is in understanding that the literal interpretation does not lead to a description of the way things ARE... it leads to a description of the way they THOUGHT things are. It leads to a naive description of reality, concocted by people who were doing the best they could with what they had.
It is absolutely appalling, though, to realize that hundreds of millions of people, TODAY, including participants in this forum, ACTUALLY BELIEVE that this mythological nonsense is actually TRUE.
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"Myth has been needed precisely because we were not in a position to understand the universe on its own terms, through the language of natural law and direct examination of its workings on a material, rational level. Once that process of understanding is completed—and we are well on our way to achieving that—the use of myth can be discarded. Its continuing retention is already proving to be counter-productive." - Earl Doherty
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