The Ten Plagues and Egyptian Ecology

When the enslaved Israelites seek to leave Egypt, Pharaoh says no. The Lord then visits ten plagues upon the Egyptians until, finally, following the death of the first born males, Pharaoh permanently relents. Some of the plagues are the types of disasters that recur often in human history—hailstorms and locusts—and therefore appear possible and realistic. Others, less realistic, border on the comic—frogs and lice. Still others are almost surrealistic—blood and darkness—and appear highly improbable.

Is it possible for this to have any basis in historical or physical reality? Can the plagues, including the less realistic and surrealistic ones, be explained as rare but attested natural phenomena?

The Plagues as Natural Phenomena

As noted by Greta Hort, one thing that stands out about the Egyptian plagues is their relationship to natural phenomena (or disasters) that occur in Egypt’s ecosystem.[2] Following this train of thought, the first six plagues can even be explained in their sequential order.

Plagues 1-6

The naturalistic account is connected initially with the violent rainstorms that occur in the mountains of Ethiopia, to the south of Egypt.

1. The first plague, referred to as dam, blood, was caused when red clay swept down into the Nile from the Ethiopian highlands coloring the river and rendering its water undrinkable.

2. The mud affected the aeration of the water that lead to the death of fish. Bodies of dead fish clogged the swamps inhabited by frogs. The rotting fish crowded the frogs out from the swamps. They left the Nile and sought cool areas in people's houses: the second plague. But, the movement of frogs occurred only after they had become infected by some communicable disease.

3-4. Since the frogs were already infected with the disease, they died in their new habitats. As a consequence, lice, the third plague, and flies, the fourth plague, began to multiply, feeding off the dead frogs.

5. This gave rise to a pestilence that attacked animals, the fifth plague, because the cattle were feeding on grass that by then had also become infected.

6. In people, the symptom of the same disease was boils, the sixth plague.

Plagues 7-9

A second sequence of plagues, according to this explanation, is related to atmospheric and climatic conditions in Egypt.

7. Although not common, hailstorms do occur rarely in Upper Egypt and occasionally in Lower Egypt during late spring and early fall.[3]

8. The hailstorm was followed by the eighth plague, locusts, a more common occurrence.

9. The ninth plague, darkness, was a Libyan dust storm.

Plague 10

10. The final plague, the death of the first-born, although not strictly commensurate with the other plagues, can be (poorly) explained in ecological terms as a reflection of the infant mortality rate in ancient Egypt.[4]

Where this Explanation Falls Short

This ecological explanation of the plagues does not prove that the biblical account is based on actual events, but only that it may have some basis in reality. It firmly anchors the plagues—especially the first 6—in the Egyptian ecosystem, just as the curse-lists in the Torah reflect real conditions in the Land of Israel. (More on that another time.)

The ecological explanation does, however, have serious weaknesses.

• The blood plague must be interpreted metaphorically.
• The ecological chain is broken after the sixth plague, since there is no causality between the plague of boils (the sixth plague) and the hail (the seventh plague).
• The chain is again broken between the ninth and tenth plagues.
• There is no real link between the plagues in the seventh-eighth-ninth sequence (hail-locusts-darkness).
• The ninth plague, darkness, must also be interpreted metaphorically if it was caused by a sandstorm.
• Only the first-born die in the Bible's account, rather than general infant mortality reflected in the ecological explanation.

An additional weakness of the "natural disaster" explanation is that some begin only after Aaron waves his staff (plagues 1-3), some only after Moses waves his hand and staff (plagues 7, 8, 9), and some by God (plagues 4, 5). Plague 6 is brought on by Moses. The plagues are turned on and off by God, but are usually announced by Moses and Aaron. Plagues 3, 6, and 9 are brought on with no warning.

No matter the origin of the ten plague tradition and its possible basis in some natural phenomena,the plagues are used in Shemot to create narrative tension—Will Pharaoh let them out this time or not? —and to provide increasingly dramatic stepping-stones that lead readers to the final great scenes: the exodus from Egypt, the crossing of the Reed Sea, and the giving and receiving of torah at Sinai

Further Complications: Plague Traditions in the Psalms

Two other detailed accounts of the plagues in the Bible, which appear in Psalm 78:44–51 and Psalm 105:28–36, further complicate the picture. These psalms differ between themselves; they also differ with the narrative in Exodus—regarding what constitutes a plague, the order in which they occurred, and the number.

The differences between these two lists suggest that the specific number and order of the plagues was less important to the Israelites who wrote and the Israelites that listened to these psalms in the Temple than the fact that plagues had occurred.[5]

A comparison of the three different presentations of plagues indicates plasticity in the Israelite tradition. The coexistence of conflicting, somewhat contradictory, parallel plague traditions suggests that the plagues should not necessarily be explained as one set of connected natural catastrophes.

Although it seems likely that some natural disasters ultimately lie behind the various plagues, the traditions in their extant forms cannot be employed to reconstruct exactly what occurred. The implication of the three lists of plagues is that Israel did not preserve the details of the plagues or their number for their own sake, but rather recalled the significance of the plagues as events demonstrating a theological principle.

The Origin of the Plague Tradition

Despite the above problems, the plague tradition includes calamitous events that do not derive from experiences in the Land of Israel; this establishes a prima facie case that at least part of the tradition has roots in an ecological system unknown to the Israelites living in their own land. Moreover, an Egyptian milieu not only provides a basis for explaining the plagues in terms of natural phenomena, it also allows us to link at least some of the sequences of plagues.

These two points lead me to conclude that a vague historical kernel may underlie the Egyptian plague traditions preserved in the Bible. But, they allow me to speculate a bit further:

Perhaps a series of natural disasters occurred in Egypt in a relatively short period of time. Egyptian religion would have had to explain it. The Egyptians may very well have seen such disasters as an expression of their gods’ displeasure.[6] No matter how Egyptians interpreted these disasters, however, local Hebrew (or Israelite) slaves may have seen them as an expression of anger by their patron deity against their Egyptian taskmasters.

Over the years, the plague traditions, maintained in oral retellings by the Israelites until some time after the establishment of the monarchy, continued to be reworked in the land of Israel. There, far from the ecological context of Egypt, some phenomena natural in Egypt would have appeared incomprehensible to them, and even fantastic, inviting embellishment. In the emerging story, their patron deity figured large.

Eventually, a narrative gained shape in which God, creator of the world and master of all natural forces within it, became the ultimate hero. Working through Moses, the story, complete with warnings to Pharaoh from God’s emissary Moses, emerged. This rounded out the story of the miraculous punishment of the Egyptians by the God of Israel. Thus, a story that began with an escape of slaves from Egypt after a period of natural disasters became, over time, a story of Israel’s release from bondage through the miraculous intervention of their patron God, YHWH, and his servant Moses.

Within the story, the stated objective of the plagues was to provide the Egyptians a lesson: "...and the Egyptians will know that I am YHWH when I stretch my hand against Egypt..." (Exod 7:5). In retrospect, however, the biblical narrator makes clear that the lesson was learned by Israel: "...and Israel saw the mighty act which YHWH had done in Egypt, they feared YHWH and believed in YHWH and in his servant Moses (Exod 14: 31).