Science Ch.28 - Explaining the Exodus Miracles

Attempts to explain these miracles don’t work very well, but we aren’t wrong to try – the Bible itself explains how the Jordan dried up (in a way that was understandable at the time). The most spectacular element in these miracles is their exact timing.

A film crew from National Geographic unexpectedly turned up at my workplace. “We’ve just come from the wind tunnel in the engineering department to witness the Red Sea parting. Now we’re here to film the burning bush.” After a stunned silence, I remembered seeing Professor Sir Colin Humphreys in the building and realized they wanted him. His professional expertise as a chemical engineer got him a knighthood, and he is equally famous for his work on science and the Bible. As well as writing popular books, he sets himself the goal of publishing his work in peer-reviewed science journals. He has been remarkably successful.

       I don’t think there is anything wrong with “explaining” miracles by trying to find out how they happened – the Bible itself does this occasionally, as we’ll see below – but it can spoil their effect. It’s rather like explaining a magic trick – as soon as you see how it’s done, the mystery and wonder disappear. I can see why the Magic Circle expels members who reveal these secrets. However, when you do understand how a trick works, you can end up admiring the ingenuity or dexterous skill of the showman, who had to create intricate devices and spent many hours practicing in order to create the appearance of magic. Similarly, when we know how God did something, it doesn’t necessarily reduce our wonder at his power, because it reveals the mechanisms through which he exerted that power and control.

5-minute summary

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The burning bush

I didn’t follow the film crew to watch the bush burning, but I was curious enough to ask Sir Colin at coffee time whether it had survived. He assured me that he hadn’t left a burnt stump in the grounds, though he said that it hadn’t worked quite as well as he’d hoped – things rarely do when people are filming! The flammable chemical he put on the bush hadn’t had enough time to spread thinly. The idea is that the chemical burns slowly and produces a lot of flame, but little of the heat is directed down to the base – so the bush has fire on it, but it doesn’t burn.

       Was this what Moses saw? Apparently, some desert bushes exude a flammable oil that can be ignited by rare actions such as lightning and then burn like Sir Colin’s chemical. Perhaps, instead, the flames were put into Moses’ mind, or perhaps God created a special fire-retardant bush and then directed a heavenly flamethrower at it. The problem is that just thinking of these options spoils the whole effect. We lose the wonder and the theological significance – that God wanted to reveal himself to Moses in order to rescue the Israelites from Egypt.

       However, according to the Bible text, Moses was just as curious as we are about what was actually happening. It says: “Moses saw that though the bush was on fire it did not burn up. So Moses thought, ‘I will go over and see this strange sight – why the bush does not burn up’” (Exod 3:2-3). When he had gotten closer, God called to him, and then Moses hid the bush from his view because he feared looking at God. And yet God hadn’t discouraged him from looking – in fact, he had deliberately attracted Moses’ attention in this way. God does not mind us looking closely and investigating how he works. We see this elsewhere because the Bible sometimes tells us a remarkable amount about how God works, within the narrow limits of what we can understand.

The plagues

The plagues that came to Egypt are mostly described in mundane terms. Some of them are awesome, such as the thunderstorms with deadly hail, or the dense dark clouds that caused total darkness. But most of them evince disgust rather than awe: frogs, lice, swarms, cattle disease, and boils. They are all nasty, but not terribly dangerous – except for the hail, when Moses warned everyone to stay indoors (Exod 9:19). The point of these miracles was partly to annoy Pharaoh until he complied, and partly to show by the timing of events that God was in total control. Moses warned when each plague would come, then did something such as waving his staff to start the plague, and finally prayed to God to end it. All this showed that they came from God. So Pharaoh gradually recognized that Israel’s God controlled these frightening aspects of nature. It was clearly Israel’s God because these plagues didn’t happen in Goshen, where the Israelites had their farms (Exod 8:22-23; 9:4).

       The final plague is completely different, and it is this one that convinces Pharaoh that he cannot withstand God’s will. This not only resulted in massive human death, but also demonstrated God’s total control over events by affecting only the eldest son in each household. This miracle stands out from the others, and it is meant to. It was intended to portray what happens when the mercy and patience of God run out. Pharaoh is described as “hard-hearted” (i.e., stubborn), and the theme of God’s control is emphasized by saying that God enabled him to remain this stubborn. However, the text also says that Pharaoh hardened his own heart (Exod 9:34-35), which implies that God was merely helping him to keep going down the destructive path he had chosen. Of course, this makes us wonder why God would want Pharaoh to stick to his plan. We can only conclude (as Paul did) that God wanted to glorify himself (Rom 9:22-23) – that is, he wanted to show Israel a miracle they would never forget and that would give them courage in tough times.

       These plagues are not portrayed in the language of miracles, except with regard to their timing and their ferocity. We’ve all experienced gnats and swarms of insects, and many people experience boils, life-threatening hailstones, locust plagues, and livestock diseases. The blood-red river sounds unnatural, but this would also be the way to describe a river swamped by red algae, which, in sufficient concentrations, can kill fish and taste bitter.1 The Bible text makes clear that all the water in the Nile and drawn from it was affected, but water in boreholes was fine (Exod 7:24). This suggests that water that had not been in contact with the Nile before the problem started was not affected. It would also fit with the idea that this was due to algae, because algal spores would be in any pots of water that had been drawn from the Nile – and would be ready to bloom at the same time – but they would not be in ground water.

       Because the Bible text itself provides these clues, I am encouraged to look for this type of explanation in it. Sometimes it even gives an explanation of its own, such as with the plague of locusts. When Moses stretched out his staff, the locusts didn’t appear immediately, but the wind changed direction, and a day later the locusts arrived in that wind (10:13). When Pharaoh begged Moses to pray, “the LORD changed the wind” (10:19) again and the locusts were removed.

       The plagues also follow a natural order. After the Nile waters became uninhabitable, frogs moved inland and even into people’s houses and kitchens (8:13). After these died and left piles of rotting corpses (8:14), the country suffered gnats and swarms of larger insects (8:16-32) – as you might expect. These insects landed “on people and animals” (8:17), after which the livestock became diseased, and people suffered boils (9:1-12). These logical progressions are not just created by a modern mind looking for explanations. They are instances of cause and effect we are encouraged to see in the text itself, which says things like, “The frogs died. … They were piled into heaps, and the land reeked” (8:13-14). Not only is God portrayed as able to control nature, but he uses nature in a natural way – albeit with supernatural magnitude.

Parting the Red Sea

Parting the Red Sea appears to be something that goes totally against anything seen in nature. We are presented with an image of walls of water that dwarf the Israelites as they hurry across and that later collapse on the Egyptian chariots. This scenario is completely unnatural – but it is also unbiblical. What we see in our minds is the imaginative creation of artists and movie makers.

       The Bible text doesn’t refer to what we call the “Red Sea,” but the “Reed Sea” (Exod 13:18 – see the NIV footnote). The Red Sea, which divides lower Egypt from Saudi Arabia, is about two hundred miles wide for most of its length, and two miles deep – which is much more than one night’s walk! The narrower Gulf of Suez separates most of Egypt from the Sinai Peninsula. This is about twenty miles wide at the southern end, then narrows to a river and string of shallow lakes at the northern end.

       We can’t be sure exactly where Israel crossed this waterway. The text appears to pinpoint the spot by naming nearby locations (see Exod 14:2), but the identities of the various places have been lost in history. This may seem strange given the amount of history that has been preserved, but even the former Egyptian capital city of Itjtawy has only just been rediscovered using NASA images, along with thirty-one hundred other settlements, most of which haven’t been identified by name.2 So it isn’t surprising that most of the locations on Israel’s exodus itinerary (some of which may be no more than an oasis) are no longer identifiable.

       However, one very important clue lies in the name the Bible gives to the stretch of water: the Yam Suph, or “Sea of Reeds.” We may not know where this is, but the name tells us something very important: there were reeds growing in it, which means it was shallow, at least at the edge. Also, the fact that chariots followed them means that the sides can’t have been very steep. This is both a solution and a problem. It makes it more likely that people could cross it, but much less likely that their pursuers would be overwhelmed and drowned by it.

       The Bible text solves this problem by stating the method used to allow the Israelites to cross and also for drowning the soldiers. It says a strong wind blew all night to part the waters (Exod 14:21). This is something that is perfectly possible with shallow water – as Sir Colin demonstrated to the film crew in a wind-tunnel simulation. Of course, it doesn’t exactly create two “walls” of water, to which the text refers (Exod 14:22, 29). The Hebrew word for “wall” is normally used for city walls, so we can forgive those artists and movie directors who have imagined two cliff-like edges of water. However, the same word is also used for other barriers, such as when David’s men gave protection to shepherds, who described them as “a wall around us” (1 Sam 25:16). So a wall of water could refer to whatever held that water back and formed a visible edge where the water stopped.

       But when the wind stopped in the morning so that the waters could flow again, would this overwhelm and drown the soldiers? The wind-tunnel experiments confirm what is seen occasionally in nature: when water has been held back in this way and is suddenly released, it sweeps forward with a high wave driven by all the pent-up energy of the water behind it. This would have crashed into the soldiers like water from a burst dam, so it is unsurprising that they were totally overwhelmed and all drowned.

       I’m afraid that I do prefer Cecil B. DeMille’s portrayal, because it seems much more exciting. But our imagination should be guided by what the Bible actually says.

Crossing the Jordan

There is one miracle from Israel’s journey to Canaan where we don’t just get a clue about how it was done: the crossing of the Jordan is explained clearly for anyone with a little local knowledge. The Israelites had to cross this river forty years after the exodus because it separated the wilderness from the land that was going to be their home. The timing was really bad, because they arrived during the spring floods, when the river was moving fast and overflowing its banks (Josh 3:15). The priests carrying the ark of the covenant were told to walk in front and stand in the middle of the river until everyone had crossed. So they walked toward the fast-flowing river, and when they reached it, the water simply stopped arriving. The text says that “the water from upstream stopped flowing. It piled up in a heap a great distance away, at a town called Adam in the vicinity of Zarethan, while the water flowing down to the Sea of the Arabah (that is, the Dead Sea) was completely cut off” (Josh 3:16).

       Someone who knows the area would know that when the Jordan passes near the town of Adam (modern-day Damiya, eighteen miles north of their crossing), it bends around a steep slope of loose mud and stones. Every now and then a section of the steep bank collapses and dams the river; then, after several hours, the water breaks through and pushes the mud aside. This is a very rare event – it has only been recorded in 1927, 1906, 1834, 1546, 1267, and 1160, though no doubt it has occurred several more times without being noted – but the possibility is obvious to anyone who sees the site.3 This account was first written for people who knew the area, so for them this wasn’t merely a description of what happened but a full explanation.

       By telling us this, the Bible text is emphasizing that the miracle lay in the timing. This is confirmed by the way the text describes the event: “as soon as the priests who carried the ark reached the Jordan and their feet touched the water’s edge, the water from upstream stopped flowing” (Josh 3:15-16). And then it explains how it happened by telling the reader the location where it was cut off.

       In the end, it is all right to seek “explanations” of miracles, partly because the Bible text itself encourages us to look for them and partly because it shows that God is able to control the real world that I live in. If the exodus was a totally extraordinary event – that is, one that looked like something from a fantasy novel – then this would make God’s activity remote from my life. But when I see that God is manipulating the same world that I live in, and using the forces that he, as Creator, has made, then to me this brings his activity much closer to home. I doubt that God will ever send winds or landslides to dry up a waterway for me to cross, but he may well manipulate the weather in ways that benefit me.

       This doesn’t mean that I want God to change the weather or control plagues of insects whenever I ask. I don’t expect this because I’m not important enough, and changes in a weather system affect a lot more people than me. Also, I don’t expect it to happen often for other people, because the Bible suggests that God works like this only occasionally. We read that “the LORD drove the sea back with a strong east wind” (Exod 14:21), and he “made an east wind blow across the land” (Exod 10:13). This shows us God stepping in at key points to change things. We shouldn’t infer from this that he manipulates every detail minute by minute. He has created his universe to work well, and most of the time it does. However, many flaws were introduced through our sin, so sometimes, as these texts show, God needs to step in and take control. Most of the time we can praise him for his faithfulness in creating a world that runs predictably. But occasionally there is no better explanation than to say that God has stepped in, and it’s a miracle – even if we can “explain” how it happened.


• Moses was curious about how the burning bush worked, and our curiosity about how other miracles work is encouraged by details given in the text.
• The plagues of Exodus follow a logical sequence, and hints in the text encourage us to regard each one as the cause of the next, with miraculous timing.
• The parting of the “Red Sea” is understandable if this is indeed the Sea of Reeds (as the text says), and the parting of the Jordan is explained by the text itself.
• Proposal: God’s miraculous interventions are seen in the timing and placement of these events: the plagues happened exactly when Moses said and didn’t extend to the homes of Israelites, and waters parted exactly when and where Israel needed.

1^ Red algae closed an Australian beach in 2012. See “Red Algae Bloom Closes Sydney, Australia, Beaches,” Huffpost, November 27, 2012 ( Rivers have also turned red from other causes such as minerals. See “Red Water,” Damage Control (
2^ See Mark Millmore, “Newsletter 54 Finding the City Itjtawy from Space,” Discovering Egypt, September 23, 2016 (
3^ See Bryant G. Wood, “Did the Israelites Conquer Jericho? A New Look at the Archaeological Evidence,” Biblical Archaeology Review 16 (1990): 44-58 (

This was previously published in a similar form in Christianity magazine

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