What is the basis for a mythical reading of Genesis 1-2?

myth: a symbolic narrative, usually of unknown origin and at least partly traditional, that ostensibly relates actual events and that is especially associated with religious belief. It is distinguished from symbolic behaviour (cult, ritual) and symbolic places or objects (temples, icons). Myths are specific accounts of gods or superhuman beings involved in extraordinary events or circumstances in a time that is unspecified but which is understood as existing apart from ordinary human experience.¹

From the definition, the basis for a mythical of Genesis 1-2, is the perspective the narrative originates from man. That is to say, if one believes in a non-supernatural explanation for the existence of the "natural" world, then Genesis must be a myth since it "ostensibly" relates actual events (i.e. the events are myths, not factual) associated with religious beliefs (i.e. man created in the image of God and the existence of the Sabbath) which involves the specific account of God involved in extraordinary events or circumstances in a time that is unspecified but which is understood as existing apart from ordinary human experience.

Of course this approach should be applied to the other mythical accounts for the existence of the physical world. For example, the Big Bang should also be read as a mythical account for the existence of the universe since it is a specific account of extraordinary events existing apart from ordinary human experience.

_{1. Britannica}

In Hebrew, it is more accurate to science, and it isn’t flawed with logical inconsistencies.

The days aren’t necessarily days—throughout scripture, it is said “to God a day is like a thousand years and a thousand years like a day.” Hebrew is very big on poetry, and the authors like to use metaphors, even when they talk about solid facts. Many translators paraphrase some metaphors that can’t make sense to someone who isn’t a scholar on that topic.

It isn’t necessarily chronological either. Lots of things in scripture are put in order (including factual events). That is both a Hebrew thing and an intentional thing. Read Isaiah, and tell me how much of that is in order. Not much—the more metaphorical it gets, the less organized it is (mostly because the most metaphorical parts are prophecies that were made by prophets who didn’t receive the whole prophecy in one setting).

There really isn’t any firm Scriptural basis for the belief that Genesis 1-3 was metaphorical. Some people say that God created the heavens and the earth to look old (which makes more sense than saying it isn’t historical given how it is treated in Scripture)

I have added a helpful addition to my actual answer. Below this paragraph is a partly translated piece of Genesis one. It is based on my knowledge of Hebrew, and seeing what Hebrew scholars said about it.

א בְּרֵאשִׁית, בָּרָא אֱלֹהִים, אֵת הַשָּׁמַיִם, וְאֵת הָאָרֶץ. 1 In the beginning of Powers creating with the heavens and with the earth.
ב וְהָאָרֶץ, הָיְתָה תֹהוּ וָבֹהוּ, וְחֹשֶׁךְ, עַל-פְּנֵי תְהוֹם; וְרוּחַ אֱלֹהִים, מְרַחֶפֶת עַל-פְּנֵי הַמָּיִם. 2 Also the land existed chaotic and darkness was upon the surface of the abyss; and the energy of Powers hovered over the surface of the water.
ג וַיֹּאמֶר אֱלֹהִים, יְהִי אוֹר; וַיְהִי-אוֹר. 3 And Powers said: 'light, exist.' And light existed.
ד וַיַּרְא אֱלֹהִים אֶת-הָאוֹר, כִּי-טוֹב; וַיַּבְדֵּל אֱלֹהִים, בֵּין הָאוֹר וּבֵין הַחֹשֶׁךְ. 4 And Powers saw the light, because it was good; and Powers divided the light from the darkness.
ה וַיִּקְרָא אֱלֹהִים לָאוֹר יוֹם, וְלַחֹשֶׁךְ קָרָא לָיְלָה; וַיְהִי-עֶרֶב וַיְהִי-בֹקֶר, יוֹם אֶחָד. [פ] 5 And Powers called light Day, and darkness He called Night. And there was evening and there was morning, one day. [P]
ו וַיֹּאמֶר אֱלֹהִים, יְהִי רָקִיעַ בְּתוֹךְ הַמָּיִם, וִיהִי מַבְדִּיל, בֵּין מַיִם לָמָיִם. 6 And Powers said: 'expanse exist in the midst of the waters, and let it divide the waters from the waters.'

Please allow me to clarify the first two chapters of Genesis which will help one to understand the 'myth' of the Earth being a mere 6000 years old. I use Ussher's Chronology as a reference.

First, let me blow your mind with a new perspective on the year 4004 BC. It was not the year of the Earth's or Adam's creation; it was the year Adam and Eve were returned to the Earth from which they were created. While in Paradise, they were immortal. Once on Earth and no longer immortal, Adam lived for a long 930 years.

It is the Jewish nation that is 6000 years old, not the Earth, not humankind.

Now, for another shocking revelation. Genesis chapter two clearly states that Adam was created Before any plant life was formed. If plant life was formed on the Third Day, then Adam must also have been created on the Third Day. Read It. God later formed the creatures of the Earth on the Sixth Day and brought them to Adam to name, showing that Adam existed prior to any land creature. They were not found to be suitable companions for Adam, thus the creation of Eve. If land creatures were created on the Sixth Day and Eve was created after them, then Eve was also created on the Sixth Day. God then created man and woman in 'their' image and told them to populate the planet. Would God create everyone the same? Of course not, thus, the various races and characteristics of Sixth Day humans - giant or pygmy, dark or light, redheads or blondes or blacks, and an assortment of brunettes. Earth was not populated by the children of Adam and Eve. The Earth was already populated by Sixth Day humans in 4004 BC when they were returned to Earth.

The sons of God, Adam's descendants, married into the 'daughters of men' who became mighty men of renown, not giants. They became worshiped by those who survived the Flood, and even those descendants became worshiped because they were the descendants of the ancient ones who lived on the other side of the Flood.

Put that in your pot and cook it until you can smell the Truth of it. Read Genesis Two again and you will 'see' the Truth has been there all along. The Third Day Theory cannot be disproved.

I could post a lot of Biblical quotes, but it would take up a lot of space. Just read chapter two over until you understand that chapters one and two are the same Creation. One is what, and the second is how.

What is the basis (Biblical basis, if possible, but I'll take extra-Biblical arguments as well) for a non-historic reading?

First, I'm not theologian, but I am not aware of any Biblical basis for interpreting anything non-historically. But I'm also not not aware of any Biblical basis for the opposite conclusion. The Bible is simply silent on demanding a specific interpretation from us. That is, there is no verse along the lines of "And the Lord spoke to Moses saying 'Once people get around to separating the Bible into chapter and verse, Gen 1-2 are allegorical, but all the rest is literal.'"

(To preempt, I'm aware that at some times Jesus quotes Old Testament passages in a way which may indicate a certain understanding of the historicity of Genesis, e.g., Mark 10:6-9. But it also reasonable to argue that Jesus was merely speaking in a way his audience would really understand. Analogously, if I say "God pursues us as relentlessly as a Terminator pursues John Conner", we understand that this does not require me to believe that ChatGPT Skynet will become self-aware anytime soon.)

In a similar fashion, asking for intent of the author(s) seems to be a strawman. Without them explicitly telling us, we can only guess and reason. For me, Gen 1 - 3 seem to be clearly "myth" in the sense of a story trying to offer an explanation for the way things are today. It answers the big questions (why there is anything at all) and the simpler ones (why do all the animals have names and who named them?). It involves a lot of simple repetition just as in modern myths. I mean, compare "And God saw that it was good. And there was evening and morning, the nth day" with "I'll huff and I'll puff and I'll blow your house down!"

Lastly, I wanted to address your comment about the percentage of Christians who have taken Genesis 1-2 non-historically. I believe you may be surprised at the number. Now, first, a caveat: there don't seem to be many studies which ask a variation of "Do you take Gen 1-2 historically?" but there are plenty on people's belief in evolution. The two topics aren't exactly the same (e.g., one could believe that God created the Earth in 6 literal days about 10,000 years ago, and then that regular Darwinian evolution has occurred since then), but I think they are close enough to make my point.

First, historically, many of the Church fathers were willing to accept a non-literal reading of Genesis 1-2. See, e.g., this paper for indication on how Augustine, Thomas Aquinas, and Calvin felt about it.

Second, even in modern times, many Christians are accepting of some form of evolution. For example, according to Pewresearch, depending on how the question is phrased, either 69% or 86% of American Catholics affirm some form of evolution. Among American white evangelicals, these numbers change to 31% or 62%. According to this study, almost 36% of self-identifying Christians world-wide accept some form of evolution, with 71.4% of European Christians believing in some form of evolution. I understand that 36% < 50%. But, still, over 1/3 of Christians accept some form of evolution.

Note: I misunderstood the question and gave an answer not based in the intent of the authors. I'll keep my original below for reference. My new answer will be brief.

Regarding the intent of the authors, we first have to clarify who they might be. Traditional Christianity and Judaism hold these stories come directly from God through Moses. Few who hold this view would consider the author's intent to be mythical. Critical scholars, using the documentary hypothesis see the author of Gen. 1 as a priestly author who was influenced by Babylonian mythology [see below]. Gen. 2 is generally seen as belonging to "J" who wrote a few centuries earlier.

Gen. 1 has been interpreted as a creation story intended to affirm God's absolute sovereignty. It appears to consciously rework the Babylonian myth contained in Enuma Elish that the Cosmos evolved from the union of the primordial mating of the original divine couple, Apsu and Tiamat. If so, the author was aware that he was, in effect, "remythologizing" a Babylonian cosmogony. In his version there is only One God hovering over the Deep in the beginning, not Two who comingle their waters as lovers do. The epochal struggle of the gods over six generations becomes the six days of creation by a single deity. The heavenly bodies are not placed in the sky by Marduk during the sixth epoch but by God [Elohim] on the fourth day. The gods don't rest because Marduk creates humans to serve them, but God rests because, after creating humans, he is done with his work of creation.

Gen. 2 [again see below] can be understood as a mythical polemic against goddess and serpent worship. If this is true, then the author intentionally recast the old myths and created a new one. As Campbell points out, in the older stories, the Goddess freely offers the fruit of sacred tree to the Man, and the Serpent is not a bringer of death but life. In Genesis, the fruit is forbidden to humans by Yahweh and the serpent is cursed for offering it to them.

Also, if the author of Gen. 2 was aware of the myth of the goddess Ninti, he may have recast it in story of "Adam's rib" and called Eve by the same title (Mother of all living) as the goddess.

The above are some of the data used by historians of religions to show that the authors of Gen. 1-2 were consciously updating existing pagan myths for a Jewish audience. If this is what happened, then these authors probably did intend them to be understood as "myths" in the sense of a stories conveying a profound truth, but not as a "myth" in the sense of something that is basically untrue.

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my original answer

The supposed mythical basis for Gen. 1 and Gen. 2 should be addressed separately. A key to understand the theory is that the primitive myths were originally cast in a polytheistic fashion while the Biblical story is told in the context of monotheism. So the roles played by the various polytheist gods are retold with Israel's God taking the central role.

GENESIS 1

Modern scholars often see the mythical base of Gen. 1 in the Babylonian Enuma Elish, translated as "When on High."

The Enuma Elish begins with a creation myth that has some elements in common with Gen. 1. It describes two primeval gods: Apsu (god of fresh waters) and Tiamat (goddess salt waters) who merge and so bring about creation. The idea of God's spirit "hovering over the face of the waters" and bringing order out of the void of chaos is thought to derive from Enuma Elish's vision of Apsu and Tiamat generating primordial creation.

When the height heaven was not named, And the earth beneath did not yet bear a name, And the primeval Apsu, who begat them, And chaos, Tiamut, the mother of them both; Their waters were mingled together.

And no field was formed, no marsh was to be seen; When of the gods none had been called into being, And none bore a name, and no destinies were ordained; Then were created the gods in the midst of heaven... [Tablet 1]

The six days of creation in the Genesis story is likewise seen by some historians of religion to parallel the six generations of gods in the Enuma Elish myth. This analysis comes from the story of Marduk, the storm deity roughly equivalent to the Canaanite Baal, who emerges after the sixth generation. Although he is a young god, he becomes dominant. He places the stars in astrological order, creates humans to be the gods' servants and thus finally allows the gods to rest. In the monotheistic story, of course, God (Elohim) makes man on the sixth "day" and then rests from his labors.

GENESIS 2

The mythical elements of Gen. 2 are more varied.

• The goddess Ninti, (Sumerian = Lady Rib) is birthed by a male god, Enki, who eats a deadly fruit and nearly dies. After she heals him, Ninti is given the title of the "mother of all living." The parallel to Eve is clear: she was born from Adam's rib and was called by the same title as Eve. (Genesis 3:20) A deadly fruit is also involved in the Genesis account.

• Joseph Campbell and others have suggested the serpent in Gen. 2 is a revamped symbol of fertility and healing seen in mythology throughout the Levant and Egypt.

The serpent, who dies and is resurrected, shedding its skin and renewing its life, is the lord of the central tree, where time and eternity come together... We have Sumerian seals from as early as 3500 B.C. showing the serpent and the tree and the goddess, with the goddess giving the fruit of life to a visiting male. Joseph Campbell > Quotes

An key to explain the denigration of the serpent in the Genesis story may be found in the story of the bronze serpent that Moses made (Numbers 21:8) and its ultimate destruction by King Hezekiah. (2 Kings 18:4) The theory is that Israelite religion was originally quite diverse, accommodating a healing Egyptian serpent god and a female god as a counterpart to Yahweh. However, once the Israelites began to formalize their religion along biblical lines, the serpent had to be excluded. So too, goddesses and priestesses could not longer be tolerated. Thus the Goddess was transformed into a woman who disobeyed God and brought sin to the world; and the serpent became God's enemy. The serpent that Moses made had to be destroyed.

The idea that key biblical stories evolved out of Babylonian, Canaanite and Egyptians myths, of course, is repugnant to many Christians. These theories, however, are consistent with the Documentary Hypothesis which sees Gen. 1 as being written in Babylon during the Exile, and Gen. 2 written sometime about the 9th century b.c.e. The reforms of Hezekiah come a century of so later and represent the growing influence of the ideology represented in Gen. 2. The Babylonian creation story promoted in Gen. 1 was introduced relatively late in the redaction process either during or after the Babylonian exile.

Christians and Jews who reject such speculation may consider that Abraham, the "father of faith," came from the Babylonian city of Ur. Since his father was reportedly an idol maker, it is nearly certain that Abraham knew the Babylonian creation myths well. As he or his descendants interpreted them under the guidance of the Holy Spirit in monotheistic context, they eventually took on the form they have in the Bible.

You can't get much more traditional (short of being in the Bible) than St. Augustine, and he addressed the issue of Genesis 1 as literal history in his treatise On the Literal Meaning of Genesis. https://www.amazon.com/41-St-Augustine-Vol-Christian/dp/0809103265?asin=0809103265&revisionId=&format=4&depth=1

Augustine first points out that all scripture is at least figurative, and then sets out to address whether whether Genesis 1 is also literal.

He didn't have the benefit of science, but he was able to find numerous problems with literal interpretation. "And evening and morning were the first day": what time zone was God in? "God created the heavens and the earth...and the earth was without form and void": something exists, but has no form -- what does that mean? "And God said, let there be light": but this is before things had form -- were those words spoken into literal air by a literal mouth, but air didn't exist yet?

He never gets to laying down the law, saying it has to be his way, but he does lean clearly to some conclusions.

One is that the sequence is not chronological but logical. Chronologically, existence can't precede form as everything that exists has form, but logically, form depends on existence.

Another is that if you start telling nonbelievers that they can't believe in Christ unless they believe stuff that is obviously wrong, like the "Manichaeans," watch out: they might believe you. :)