We all know that:

Ancient Near Eastern people believed that the sky was a strong solid dome or firmament, holding up heavenly waters above it. This teaching is reflected in Genesis 1:6–8:

And God said, “Let there be an expanse in the midst of the waters, and let it separate the waters from the waters.” And God made the expanse and separated the waters that were under the expanse from the waters that were above the expanse. And it was so. And God called the expanse Heaven.

In his new book, Interpreting Eden, Vern Poythress argues that both of these premises are wrong.

We have no good evidence that people of the ancient Near East actually held this view. And Genesis 1:6–8 does not teach or presuppose it.

Here’s a summary of his positive interpretation of that passage:

The “expanse” (רָקִיעַ) in Gen. 1:6-8 is the same as “heaven” (שָׁמַיִם, verse 8). Both words refer flexibly to what it above us. (The word heaven can also refer to the invisible dwelling of God with his angels.) Depending on the context and the weather and the time of day or night, we may see clouds (by day), sun in a blue sky, stars and sometimes the moon in a black night sky, and black sky when there is a cloud cover at night. In many contexts the word heaven (שָׁמַיִם) is roughly equivalent to our modern English word sky. We can comfortably speak of a cloudy sky, a blue sky, a fiery sky (at sunset), and a night sky. Likewise, the Hebrew term for heaven covers the same spectrum (1 Kings 18:45; Gen. 1:14-15).

The expression “waters that were above the expanse” primarily designates water above a cloudy sky, that is, water inside clouds, whose lower side is the sky. (But it is left open whether there is also invisible water.)

All this makes sense to an ancient Israelite as well as a modern reader with appropriate understanding of the point of view and kind of description that Gen. 1:6-8 offers. Gen. 1:6-8 gives us an ordinary description, a phenomenal description, a description of appearances, and does not offer any detailed “theory” about the expanse (“heaven”) or the water above it.

Genesis 1:6-8 becomes intelligible when we realize that it works with analogies between creation and our present experience of God’s providence in bringing rain.

From there he goes on to examine in some detailed the proffered parallel texts in ANE literature that supposedly show what the ancients believed, and shows how a physicalistic interpretation has been anachronistically imported into them, especially Genesis.

If a person expects physicalistic information in ancient mythic texts or in the Bible, he can “find” what he expects. But if we are not expecting an explanation in terms of physical mechanisms, we can approach the same passages in a different way: they are imagistic, colorful pictures. They are part of a larger pattern, according to which the Old Testament uses analogies between the cosmos and a house or a tent.

Poythress then offers nine principles that are at play in guiding how we should interpret a phrase like “the waters above”:

Israelites could be expected to have some knowledge about rain. Old Testament passages show that Israelites knew that rain came from clouds. Other materials from the ancient Near East confirm that people of that time were familiar with the idea of rain coming from clouds. The Bible sometimes describes rain as coming from “heaven.” The Bible uses language about the heavens being “shut” to describe a situation with lack of rain. In a manner analogous to the heavens being “shut,” the Old Testament may describe rain as coming when the heavens are “opened.” Israelites thought of dew as another form of provision of moisture “from heaven,” more or less parallel to rain. In general, the Old Testament instructs Israelites about things that affect their lives. Genesis 1 speaks about things relevant to Israelites.

Poythress concludes:

In Genesis 1 as a whole and in Genesis 1:6-8 in particular God speaks about acts of creation that not only evoke praise but have practical interest to human beings. Thus Genesis 1:6-8 is speaking about water above, such as Israelites received from clouds. The alleged heavenly sea is irrelevant, and so it must be rejected as not pertinent to interpreting 1:6-8.

In fact, introducing a heavenly sea creates interpretive problems rather than solving them. Once we acknowledge that Israelites knew that rain comes from clouds, a modern theory about the heavenly sea has to postulate not two bodies of water, but three: the sea on earth, the water inside the clouds, and the heavenly sea. It has to say, in effect, that Gen. 1:6-8 mentions the first and the third, even though the third is irrelevant, while leaving out the second, which is continually relevant for crops and for herds. May we ask whether this interpretation is plausible?

Finally, we may observe that an interpretation of Gen. 1:6-8 as a reference to a heavenly sea violates the key principle that Gen. 1 teaches about creation using analogies from providential experience. There is no providential experience of a heavenly sea, whereas there is providential experience of rain descending from clouds. The implausibility of the heavenly-sea interpretation increases because of its lack of contact with ordinary experience. In reality, the heavenly-sea interpretation imposes an alleged ancient quasi-scientific physicalistic theory of the heavenly sea on the text, which is just as bad as imposing on the text the expectation for modern scientific-technical precision.

Since we cannot go back and interview ancient Israelites, modern interpreters can always postulate that the Israelites had strange beliefs about a heavenly sea. Such postulates are likely to be around for a long time. The postulates have become embedded in the tradition of Old Testament scholarship. They seem at first glance to be supported by various ancient Near Eastern texts, at least if the texts are read physicalistically. The postulates are further sustained by the modern myths that make us complacent about our superiority to the ancients and patronizing toward their alleged primitive naiveté. But, if we are alert, we may entertain doubts. Whether or not the Israelites had strange beliefs, God does not address such beliefs directly, and neither does he presuppose them. He teaches that there is water above, separated from water beneath by an expanse. The language is sparse. If any ancient Israelites or modern interpreters do not realize that rain does indeed come from water above, that is their problem.

You can read the whole argument with extensive documented detail here.