Category: Religion and Science

Q. There are two verses in the Bible that I’ve often seen used as proof texts to argue that science, done properly, will ultimately be compatible with any descriptions of nature (including creation) that are found in the Bible.

Psalm 19:1 – The heavens declare the glory of God; the skies proclaim the work of his hands.
Romans 1:20 – For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made.

In your view, what is the best interpretation of these verses? For example, in what ways do the heavens declare the glory of God and how have God’s invisible attributes been “clearly seen… from what has been made”? Should these verses be understood to be making broad claims about the existence of God from the existence of anything rather than nothing? Are they making other esoteric arguments from aesthetics and beauty? Would the biblical authors even have had these kinds of philosophical/apologetics-type arguments in mind, or does that import modern concepts into the text?

Psalm 19 does not say, “The heavens declare the existence of God.” It says, “The heavens declare the glory of God.” The psalm considers the existence of God a given, and it addresses people who also consider that a given. It is not speaking to the question of whether there is a God; it is speaking to the question of what God is like.

The psalm does not say specifically in what the “glory” of God consists that the heavens “declare.” However, we may infer something about this from the use of the sun as a specific instance of the general principle. The psalm seems to be saying that the glory of God is seen in the way that a single celestial object can make a circuit of the heavens and light up everything beneath. This seems to suggest the idea that the creation is orderly, harmonious, even beautiful, and in that way it exhibits the character of the God who made it.

The psalm pairs the statement “the heavens declare the glory of God” with the statement “the law of the Lord is perfect.” Those are the opening lines of its two halves. It has been said well that this psalm speaks of the “two books” of God, nature and Scripture. I think it is saying that we get some idea of God’s character from nature, and if we want to appreciate that character more fully and emulate it (among other things, in order to fit harmoniously into creation), we can learn about it in Scripture.

A similar observation might be made about the passage in Romans. Paul does not say that God’s existence is clearly seen from what has been made. He says that God’s qualities are seen that way.

As for arguments for the existence of God based on the idea that the universe must have come from something rather than from nothing, the Bible says, in Hebrews 11:3, “By faith we understand that the universe was created by the word of God, so that the visible came into existence from the invisible.” This is something from something, the visible from the invisible, but I think the important thing is that the Bible says we understand this by faith. It is not saying that we should expect that rationalistic, scientific endeavor will confirm the existence of God as it explores the creation.

Indeed, on its own terms, science will never confirm the existence of God. Science, by definition, limits itself to what is observable and measurable. So science will never be in a position to prove or even assert that there is or is not a God. Any purported science that claims to speak to that question has moved into metaphysics.

Interestingly, however, science, also by definition, posits an orderly universe. For example, it posits that if a series of experiments demonstrates something in one place and time, that will hold true in all places and all times. If you hold a tennis ball out at shoulder height and release it 100 times, and it falls to the ground 100 times, you have a phenomenon to explain. The best explanation we know of that right now has to do with gravity. But no one is concerned that the ball would have risen rather than fallen if the experiment has been done for a 101st time.

I heard an excellent talk once that said that science cannot prove that the universe is orderly, and it certainly is not in a position to explain why the universe is orderly, assuming that it is, but that assumption seems to hold true, and it has produced useful results for many centuries, and so science keeps working with it. That’s as much as science can say. This does agree with the biblical description of a universe that is orderly and harmonious. But the idea that the universe is that way because it reflects the character of the God who made it is something that we know by faith. That, I would say, is what the Bible teaches on the subject.

Q. I cannot reconcile the earth and the entire universe as being only 6,000 years old, and the scientific findings that the “big bang” happened billions of years ago. According to Genesis they were created within the same week. And while on the subject, surely, the all-powerful God did not have to REST on the 7th day. Fact is, He could have created all that He created in 6 days, with a snap of His fingers, if He had wanted to. What gives? Thanks.

Regarding reconciling the biblical presentation of a young earth with scientific findings, let me refer you to another blog of mine, Paradigms on Pilgrimage, which is actually a book in blog form. I wrote it with Dr. Stephen J. Godfrey, curator of paleontology at the Calvert Marine Museum, to address precisely that issue. In the book, we each tell our own story of coming to a satisfying understanding of it.

Regarding God resting, let me refer you to this post, in which I say, in part, commenting on what Exodus says about God, “on the seventh day he rested and was refreshed“:

In what way could an infinitely powerful God be refreshed, if by definition He could never get tired in the first place? Many interpreters consider the “refreshment” of God to be, in effect, the “aaah” feeling He got when He surveyed “all that He had made” and saw that it was “very good.” While God first got this overview at the end of the sixth day, He devoted the entire next day to contemplating and admiring the beauty of the entire finished creation.

Q. Apologist and philosopher Dr. Alvin Plantinga is of the opinion that the existence of a caring God is a “properly basic notion,” that is, a notion so basic that it is not dependent on other ideas or arguments, something, he claims, that is obvious to most intelligent people. The Rev. Timothy Keller seems to agree: “I think people in our culture know unavoidably that there is a God, but they are repressing what they know.”—Timothy Keller, The Reason for God (Dutton, 2008), page 146. Do you have an opinion on this matter?

I am inclined to agree with the view of Plantinga and Keller as you describe it. Personally I think that if God did not actually exist, people would not argue about whether God existed. The subject wouldn’t come up.

The Bible teaches that people form a notion of God from creation, from conscience, and from their sense that even though they are finite, they are meant to be connected with something infinite. Appealing to biblical teaching is different from saying that belief in God is a properly basic notion, but this is a blog about the Bible, so I think it is appropriate to mention that the view you are describing seems to have biblical support. “The heavens declare the glory of God, and the sky above proclaims his handiwork.” “Since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made.” “When Gentiles, who do not have the law, do by nature things required by the law, they are a law for themselves, even though they do not have the law. They show that the requirements of the law are written on their hearts.” “God has set eternity in the human heart; yet no one can fathom what God has done from beginning to end.”

Along these lines, Hannah Whitall Smith appeals to the analogy of eagles born and raised in captivity. They have never seen flight, yet they feel a compelling urge to fly. We might say that flight is a properly basic notion for eagles, just as belief in God is a properly basic notion for people. She writes, “Like the captive-born eagle that feels within it the instinct of flight, and chafes and frets at its imprisonment, hardly knowing what it longs for, so do our souls chafe and fret, and cry for freedom. … The wings of the soul carry it up into a spiritual plane of life, into the ‘life hid with Christ in God,’ which is a life … that no cage can imprison and no shackles bind.”

Q. My question is about biblical cosmology, specifically about the relationship between the sun, moon, and stars and the firmament. If we assume that the firmament is a solid dome, and the Bible says the sun, moon, and stars are IN the firmament, then it seems the sun, moon, and stars are somehow embedded in the firmament. But to an ancient Hebrew looking up at the sky, it would have been obvious that the sun, moon, and stars MOVE across the sky. A rotating firmament might seem to fix that problem, except that it also would have been obvious that the sun, moon, and stars—and “wandering star” planets—move across the sky at DIFFERENT speeds. I’m trying to make this cosmology as logically coherent as possible, and this issue bugs me. One solution I have in mind is that the firmament can be defined as both the solid dome and some of the space underneath the dome; thus, the sun, moon, and stars could move in the space just below the dome—just as Genesis say birds fly across the face of the firmament. But does this solution actually accord with the Biblical Hebrew describing the cosmology?

In our book Paradigms on Pilgrimage: Creationism, Paleontology, and Biblical Interpretation, my co-author Stephen J. Godfrey and I note this same problem. This book is now available online as a blog. I will quote from the post in which we discuss this issue. After noting that the sun first appears on the fourth day of the Genesis creation account, even though there is light on the first day, and that the moon sometimes appears during the day, even though it is supposed to “rule the night,” we say:

“But these are not the only ways in which the account of the fourth day confounds our modern cosmological expectations. Perhaps even more important is the effect of a small preposition: in. Genesis tells us that God set the sun, moon and stars in the dome of the sky. We today would instead place them beyond the sky—outside our atmosphere. Even if we grasp the idea that the Genesis author is picturing a solid sky, we might still imagine these lights shining through from the back. But the account says quite clearly that they are in the dome. The particular means by which they are attached is not specified; nor is the means by which they move through the sky. But there can be no doubt about where they are, and it is not where modern cosmology would put them. Nevertheless, it is exactly where they appear to be, to the naïve observer.”

So, even though I co-authored a book that discusses Genesis cosmology, in that book itself I admitted that I did not know precisely how the ancient Hebrews understood the sun, moon, and stars to be moving in the firmament. However, since then I have come across the idea that they were understood to move on tracks on the surface of the firmament. The Bible does not say this specifically, but that explanation may be as good as any. I think that if the sun, moon, and stars had been understood to move just in front of the firmament, then the same expression would have been used for them as for the birds, on the face of the firmament, rather than in the firmament.

I hope this is helpful. You may be interested in reading the entire section of our book that is dedicated to Genesis cosmology, which starts with this post.

Q. I have a good friend who is a non-believer. I’ve been speaking to him, on and off, for many years, but he still questions God’s existence. During a recent email exchange, here is what he wrote. How would you answer his question?

“And then I say to myself, if there is a God, why wouldn’t he make his existence clear to all mankind in the present day? … What reason could there be to not show himself to mankind now in some unambiguous way??? A way that is not subject to a few individual reporters misstating facts or creating fiction?”

Actually, according to the Bible, God already has made His existence unambiguously clear. God has done this, for one thing, by imprinting evidence of his reality and character onto his creation: “Since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse.” God has also made His existence clear by imprinting His moral laws on the human conscience. The Bible says, for example, that when people who do not have the law (that is, the Scriptures) “do by nature things required by the law, they are a law for themselves, even though they do not have the law. They show that the requirements of the law are written on their hearts, their consciences also bearing witness, and their thoughts sometimes accusing them and at other times even defending them.”

However, it is true that the witness of creation and conscience are not sufficient to convince a person of the existence of God if that person is relying on reason and empirical observation alone. The Bible says that “without faith it is impossible to please God, because anyone who comes to him must believe that he exists and that he rewards those who earnestly seek him.” Faith is a capacity for knowing that requires trust. (The same Greek word is actually translated both as faith and trust in English New Testaments, depending on context.) I think God wants us to come to him by faith because He doesn’t just want us to affirm mentally that He is real; He wants us to enter into a relationship of trust with him. So God requires the first step to be something that will lead in the right direction. Gaining knowledge, by itself, can lead to pride, which leads us away from God; coming to understand through trust leads us towards God.

In one episode of the television series Bones, the character of Dr. Brennan, who is a skeptic, insists, “Faith is the irrational belief in something that is logically impossible.” Actually, faith is just the opposite. It is the reasonable belief in something that is quite possibly true, but which can’t be proved  through reason and observation alone. It is reasonable to believe in God; I would argue that it’s actually more reasonable than to deny the existence of God: All of our experience tells us that things don’t come from nowhere, they come from somewhere. Then where did we and the universe we live in come from? So God’s existence is certainly possible and it’s arguably reasonable. But it can’t be demonstrated the way we would demonstrate a natural phenomenon scientifically.

Nevertheless, faith is indeed a way of knowing. How, for example, can I be sure that my mother loves me? She fed and clothed me right from the time I was a baby—but maybe she just didn’t want to go to jail for child neglect. She says that she loves me—but maybe that’s because that’s just what mothers are supposed to say. The fact can’t be demonstrated empirically. But because I know my mother personally, I know that I can trust that these things truly are signs of a genuine love.

It’s the same way with God. Once we begin to approach Him through trust, we discover more and more that this trust is warranted. In fact, the trust itself is a gift from God to us to enable us to get to know Him: “We know  that the Son of God has come and has given us understanding, so that we may know him who is true.”

So the next time you speak with your friend, you might suggest to him that faith is a way of knowing that will allow him to recognize that God already has made His existence clear, but that God has done this in a way that requires people to approach him through trust. Your friend might counter that God ought to reveal Himself in a way that is accessible to reason and observation, because that is what people can be sure of. However, to claim that there is nothing that can be known certainly apart from what reason and observation can reveal is itself a faith statement. It’s like claiming that there is no light beyond the visible spectrum because we can’t see anything beyond the visible spectrum with our eyes. Logically there still could be—and with more powerfully instruments it has been show that there is—light beyond that spectrum that we simply can’t see with our eyes. Similarly, logically there could be realities in the spiritual world that reason alone could not be confident of, but which could be (and indeed are) accessible to us when we use the faculty and gift of faith that God intends to be part of the way each of us knows, and trusts, and knows.

Last Saturday (April 22, 2017) I participated in the March for Science. You can see in the picture above what my sign said.

Lots of people took photos of it. Several engaged me in conversation. One person looked at the sign in near disbelief and asked, “Is that all true?” “Yes,” I replied, “I support science, and I have a Ph.D. in theology.” “Well,” she responded, “it sounds like you and I could have a great philosophical discussion some day. But in the meantime, thanks for being here.” I told her I’d felt it was important for me to be there.

Our local NPR station had a reporter covering the event. When she spotted my sign, she took my picture (that’s her photo above) and interviewed me along the route. I shared the coverage on Facebook and one person commented, “You should post an article on your blog about how exactly your theology leads you to support modern science.” I thought that was a great idea. So here goes!

As George Harrison said in the movie Help!, “I don’t want to knock anyone’s religion,” but faiths such as Buddhism teach that the material world is an illusion. We need to look past it and escape from it in order to find enlightenment and truth. The Judeo-Christian world view, by contrast, is that the material creation is a genuine reality with positive spiritual import. It was created intentionally by a good God (not by mistake by a bad demigod, as the Gnostics taught) and declared to be “very good.”

In fact, the Bible holds that creation itself can speak to us about God. “The heavens declare the glory of God; the skies proclaim the work of his hands,” Psalm 19 says. Paul writes in Romans that “since the creation of the world, God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made.” So Christian faith gives us confidence that when we observe the world around us, in effect, we can trust our eyes—what we’re seeing is not a spiritual illusion.

Beyond this, the Judeo-Christian world view is that the created world is orderly and harmonious. It’s not hopelessly swirling about in confusion and chaos. Of course the Bible, since it comes from a pre-scientific era, doesn’t say specifically that the universe is governed by rules and laws such as the Law of Gravity or the Law of Thermodynamics. (When it comes to this view of the universe, which is no longer the state of the art but which has made indispensable contributions to our understanding, we may quote Alexander Pope’s intended epitaph for Isaac Newton: “Nature and Nature’s laws lay hid in night: God said, ‘Let Newton be!’ and all was light.”) But the Bible does portray the creation as intentionally well-organized and regular, allowing observations of phenomena to be made today that will still be valid tomorrow, and permitting conclusions drawn in one area to be applied in other areas. If all were chaos instead, we couldn’t make sense of out anything.

And ultimately I would argue that Christian faith actually encourages us to go out and explore the created world. As I told the reporter along the march, I believe that science answers questions of what, when, and how, while religion answers questions of who and why. The two are not in competition because they’re answering different questions. Science intentionally limits itself to what can be observed and measured, so it does not properly get into metaphysics. (Saying that there is nothing beyond what can be observed and measured, for example, is not a scientific statement!) Similarly, the Bible was not written to give us comprehensive information about the natural world. Instead, I believe it pushes us out into that world to find the information out for ourselves.

Let me advocate for this, in conclusion, by quoting some relevant thoughts from the book Paradigms on Pilgrimage: Creationism, Paleontology, and Biblical Interpretation, which I co-authored with my brother-in-law Stephen Godfrey, who is curator of paleontology at the Calvert Marine Museum. (We have now put this book online as a series of blog posts, followed by a question-and-answer forum.)

“It is the glory of God to conceal a matter; it is the glory of kings to search out a matter.” King Solomon, who wrote these words, was noted for his natural-scientific investigations: “He described plant life, from the cedar of Lebanon to the hyssop that grows out of walls. He also taught about animals and birds, reptiles and fish.” In these days when many of us enjoy the kind of leisure for cultural, artistic and scientific pursuits that only kings formerly enjoyed, we may paraphrase Solomon’s words in this way: “God has hidden countless fascinating and wonderful things in his creation, and he wants us to delight in discovering them.” When we do, we bring him pleasure by fulfilling his purposes. So all those who are called to scientific enterprise should pursue that calling without fear or doubt, but rather with joy and enthusiasm. There is no script that you need to follow, no predetermined conclusion that your results need to square with. If there were, God would not really have “hidden” these treasures for us to find. They’re out there – go get them!

Q. In conversations with the average Christian, it appears that they are quite prone to “conspiracy-theory” type reasoning and that distrust of science is fairly ubiquitous. There is an uncanny ability to “explain away” anything that challenges their views by claiming it is caused by the corrosive effects of secularism, demon activity, atheism, hedonism, the fallibility of human reasoning, the effects of the fall on rationality, the “tentative nature” of science, etc. Do you know of a good way to reason with these types, and in the end, is it even worth it?

First, I sincerely hope that what you say is not actually true of the “average Christian.”  I’d like to think that the average or typical Christian is someone who takes seriously Jesus’ admonition to love God with heart, soul, mind, and strength, and who emulates the Bereans, whom the New Testament praises for “searching the Scriptures daily to see whether these things were so.” (That is, rather than uncritically accepting dogmatic teaching.)  I see this as the norm, and feel that taking an open-minded, logical, inquisitive stance is perfectly compatible with being a person of faith.

That much said, I have to admit that over the years I’ve encountered people who’ve appealed to all of the various considerations you list to explain away beliefs different from the ones they were holding at the time.  So what’s to be done when people clearly are not open-minded, and perhaps not even rational, in the way they engage other beliefs that are nevertheless within the spectrum of Christian orthodoxy?

One question I find helpful to ask is, “What do they think is at stake in the issue?”  For example, people are sometimes encouraged to believe that if God didn’t actually create the universe in six 24-hour days about 6,000 years ago, then nothing the Bible says about anything is trustworthy.  (The old “if you can’t trust what it says on the first page, you can’t trust anything else in the book” argument.)  And I personally would be very resistant to any claim whose implications I thought were that I couldn’t trust anything in the Bible. This is because I know for a fact that I can trust everything in the Bible, so long as I understand and interpret it properly.

The key is to make sure that I’m doing that.  But this already shifts the issue from the Bible’s reliability and trustworthiness to its interpretation.  Maybe the person I’m speaking with isn’t prepared to make that shift.  Maybe they think its trustworthiness is truly at stake.  In that case, I find it helpful to suggest that there are many things that Christians of good will, equally committed to the authority of the Scriptures, can disagree about, and to demonstrate that Christians have in fact disagreed about such things over the whole course of church history.  (Long before the corrosive effects of secular humanism set in, that is.)

For example, I might observe that we can find a disagreement in the 4th century between Ambrose and Augustine as to whether the “days” in Genesis are literal 24-hour periods.  (Ambrose said they were, while Augustine maintained they weren’t.)

This will not persuade the person who believes that the truth of the entire Bible rests on one answer to this question.  But in this conversation and others, I may be giving them an island to step onto if, at some time in the future, their ship starts leaking and taking on water. This, I think, is much better than leaving them no option other than having their entire faith go down with the ship (the current dogmatic package) if it ever sinks.

And if I maintain good will (that is, if I don’t lose my cool) and approach the question humbly and open-mindedly, searching the Scriptures with them, then I’m actually demonstrating how Christians of good will, with equal commitments to the authority of the Bible, can disagree on questions like this.  That makes things a little less high-stakes.

Don’t underestimate the value that such a demonstration will have on anyone else who might be watching the two of you talk, listening to your conversation.  You will likely have an audience larger than one.  And the discussion can also help you be more “fully persuaded in your own mind.”  It never hurts for us to have our own ideas challenged and to have the occasion to ground them even more firmly on a reasonable basis, at least to our own satisfaction.

So, as I said, if your goal is to persuade on the spot, that isn’t going to happen in the face of irrationality and conspiracy theory.  But if your goal is to provide the person with information and tools that may be useful to them farther down the road, then I think you have every chance of doing that.  I suspect that many of us start out holding our beliefs more dogmatically when we first become Christians, because we know we have received a “great salvation” and we simply don’t find anything credible that we think undermines it.  But then, hopefully, we will discover how great that salvation truly is, how many different perspectives it accommodates and even requires if we are even to begin to understand everything God is and all that God has done.  And then the adventure begins.

Here is a second question from the reader whose first question I addressed in my last post. This one is in response to my book Paradigms on Pilgrimage: Creationism, Paleontology, and Biblical Interpretation, which I co-authored with Dr. Stephen J. Godfrey.  (The book is now available free online through the link provided.) The question has several parts, which I’ll take up separately. It has been edited for length.

• Do you believe that holding to “apparent age” (rather than real age) intimates that God is deceitful?

This question addresses the possibility that God created the world only recently, but gave it the appearance of great age.  I’ve heard this argument advanced by young-earth creationists to account for why scientific investigation in fields such as geology, astronomy, etc. concludes that the earth is billions of years old:  it  looks that way, for some reason, by God’s design.  After all, the argument continues, Adam and Eve each appeared, at the moment of their being freshly created, as if they had grown to adulthood over a period of many years.  I’ve even heard it said, in an extreme form of this argument that I recognize you are not suggesting, that God made the world look old so that those who chose not to believe the Scriptures (which are assumed to teach a literal six-day creation about 6,000 years ago) would be deceived by what their eyes and eventual scientific instruments saw, and they would suffer the ironic punishment of thinking they knew the truth while all the time they were believing a lie.

Let me state very plainly that this is not the kind of God I believe in.  As my co-author and I say in Paradigms on Pilgrimage, God has filled creation with marvelous things for us humans to explore, and we can do this without ever having to wonder whether we can really trust what our eyes are seeing and our instruments are detecting.  So yes, I would say that the “apparent age” position does imply, at least to me, that God is deceitful.

• In Christianity and the Age of the Earth, Davis A. Young asserts that “in spite of frequent interpretations of Genesis 1 that departed from the rigidly literal, the almost universal view of the Christian world until the eighteenth century was that the Earth was only a few thousand years old.” Do you think these many followers of Christ were “deceived” by Scripture into believing a young-earth view?

The reason why people universally believed in a young earth before the 18th century was that until that time, they were limited to the same observational world view and cosmology as the biblical authors.  And so it wasn’t a matter of scientific or pre-scientific investigations saying one thing and the Bible saying something else (and so “deceiving” people).

What’s far more important is that, by Young’s own account, Christian interpreters of Genesis made “frequent” departures from a “literal” view.  Young-earth creationism is inextricably linked to a literal view of Genesis.  But insisting on this view is the modern innovation.  The Christian tradition offers a rich variety of non-literal interpretations, along with evidence of literal ones.

Augustine, for example, argues in The City of God that the works of creation “are recorded to have been completed in six days (the same day being six times repeated) because six is a perfect number—not because God required a protracted time, as if He could not at once create all things . . . but because the perfection of the works was signified by the number six.”  Augustine also argues that time had to have been created simultaneously with the world whose creation is measured by time, a paradox that leads him to conclude, “What kind of days these were it is extremely difficult, or perhaps impossible for us to conceive, and how much more to say!”

So an appeal to the earlier Christian tradition does not reveal a long line of people who chose to believe in a literal reading of Genesis despite the evidence of science.  Rather, it introduces us to an ongoing conversation about that book among faithful people who held a variety of positions on how literally its details should be taken.

• Jesus, speaking of himself in the third person, said, “At the beginning the Creator ‘made them male and female.’” At the beginning—not 4.6 billion years later. Was Jesus being “deceitful”? He, the Creator, was there.

Actually, in this passage, Jesus is not appealing to his own firsthand knowledge of the events of creation, but to the Scriptural account of creation, by quoting from Genesis.  He says to the Pharisees who have come to test him on the question of divorce, “Have you not read that at the beginning the Creator ‘made them male and female’?”  The main point of this passage is to teach about the permanence of marriage in God’s design, not about the age of the earth.  Any inferences we draw about that latter question must be secondary.  And even so, we should take Jesus’ reference as applying to the beginning of the human race, the time when marriage was instituted, not to the original creation of the physical world.  So the issue of how long the world was around before humans were is not really relevant to this passage.

• I believe also that the Lord gave the Ten Commandments to Moses. The “six days” of Creation are related to sabbath observance (“the seventh day is a sabbath to the Lord your God, on it you shall not do any work . . . for in six days the Lord made the heavens and the earth“). It is obvious that God did not intend for Jews to work for six thousand or million years and then rest for one thousand or million years. Creation chronology parallels sabbath chronology.

I think it’s more accurate to say that, at least according to the book of Exodus, sabbath chronology is intended to parallel creation chronology.  There are to be six days of work, and then a day of rest, because that’s how God did it, according to Genesis.  It is quite clear that Moses has literal days in mind for the Israelites to work and then rest.  But this is not dependent on the days of creation also being 24 hours long. The sabbath commandment echoes the phrasing of the Genesis creation account in several places, so it is clearly intending to draw an analogy there.  All we need to know is that there are six “days” of some sort in that account, followed by a “day” of rest, in order to draw an analogy to literal days in human living.  The Genesis days aren’t required to be literal days in God’s activity as well for the analogy to work.

We should also note that the sabbath commandment has a different rationale in Deuteronomy:  “Observe the Sabbath day by keeping it holy, as the Lord your God has commanded you. . . . Remember that you were slaves in Egypt and that the Lord your God brought you out of there with a mighty hand and an outstretched arm.”  So the biblical grounds for “sabbath chronology” are not exclusively “creation chronology.”  The sabbath is observed for reasons that grow in variety and richness as God’s redemptive purposes continue to unfold.  By the time of the New Testament, the sabbath can even be observed by “honoring all days alike” just as much as by “considering one day more sacred than another.”

Thank you very much for your interesting questions!