Natalie, I found an interesting article from the Times of Israel that talks about this in more detail.
I have copy and pasted a bulk of it here, but you can read the
Full Article for more.
My own thoughts are in purple at the bottom.The hardening of Pharaoh’s heart is referred to no less than 20 times in the course of the story of the Exodus. Sometimes it is Pharaoh who is said to harden his heart. At other times, God is said to have done so. The Torah uses three different verbs in this context: ch-z-k (Strong's 2388), to strengthen, k-sh-h (Strong's 7185), to harden, and k-b-d (Strong's 3513), to make heavy.
Throughout the ages, the commentators have been concerned with one problem. If God hardened Pharaoh’s heart, how could he have been to blame for not letting the Israelites go? He had no choice in the matter. It was God’s doing, not his. That he and his people should be punished seems to flout the fundamental principle of justice, that we are guilty only for what we have freely chosen to do.
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Rashi says that the hardening of Pharaoh’s heart in the last five plagues was a punishment for the first five, when it was Pharaoh’s own obstinacy that led him to refuse to let the people go.[1] Maimonides interprets God’s hardening of Pharaoh’s heart as meaning that “repentance was withheld from him, and the liberty to turn from his wickedness was not accorded to him.”[2] Albo and Sforno offer the opposite interpretation. God hardened Pharaoh’s heart precisely to restore his free will. After the succession of plagues that had devastated the land, Pharaoh was under overwhelming pressure to let the Israelites go. Had he done so, it would not have been out of free choice, but rather under force majeure. God therefore strengthened Pharaoh’s heart so that even after the first five plagues he was genuinely free to say Yes or No.[3]
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However, part of the truth may lie in a completely different direction.[4] The Egyptians – Pharaohs especially – were preoccupied by death. Their funerary practices were astonishingly elaborate and were meant to prepare the person for life after death. The tombs of the Pharaohs were among their most lavish creations. Tutankhamun’s, discovered in 1922, is a dazzling example. One of the greatest literary works of ancient Egypt was The Book of the Dead.
The Torah notes the attention the Egyptians gave to death...
However, there is one specific aspect of Egyptian belief that opens up an entirely new perspective on the references to Pharaoh’s heart. According to Egyptian myth, the deceased underwent a trial to establish their worthiness or otherwise to enjoy life after death in Aaru, the Field of Reeds, where souls live on in pleasure for eternity. They believed that the soul resides in the heart, and the trial consisted of the ceremony of The Weighing of the Heart. Other organs were removed after death, but the heart was left because it was needed for the trial.
On one side of the scales was a feather. On the other, was placed the heart. If the heart was as light as the feather, the dead could continue to Aaru, but if it was heavier, it was devoured by the goddess Ammit (a combination of lion, hippopotamus and crocodile), and its owner was condemned to live in Duat, the underworld. An illustration, on papyrus, in The Book of the Dead shows the ceremony, undertaken in the Hall of Two Truths, overseen by Anubis, the Egyptian God of the dead.
It follows that the root k-v-d, “to make heavy,” would have had a highly specific meaning for the Egyptians of that time. It would imply that Pharaoh’s heart had become heavier than a feather. He would fail the heart weighing ceremony and therefore be denied what was most important to him – the prospect of joining the gods in the afterlife...
One of the things the deceased were supposed to do as part of the trial was to make a series of negative confessions, 42 in all, declaring themselves innocent of the kind of sin that would exclude them from paradise. These are some of them:
I have not done injury to men.
I have not oppressed those beneath me.
I have not murdered.
I have not commanded murder.
I have not caused suffering to men.[5]
If the “heavying” of Pharaoh’s heart is an allusion to the Weighing of the Heart ceremony, it allows us to read the story in a completely new way.
First, it suggests that it is directed to Egyptians as well as Israelites; to humanity as a whole. The Torah tells us three times that the purpose of the signs and wonders was “so that the Egyptians may know that I am the Lord” (Ex. 7:5; 14:4; 14:18). This is the core of monotheism. It is not that the Israelites have their God, and the Egyptians their pantheon, but rather that there is one sovereign power in the universe.
That is the point of at least three of the plagues: the first, directed against Hapfi, the god of the Nile; the second, frogs, directed against Heqet, the Egyptian goddess of fertility and childbirth, represented in the form of a frog; and the ninth, the plague of darkness, directed against Ra, the sun god. The message of these plagues would have been clear to the Egyptians: there is a power greater than those they have worshipped until now. The God of Israel is the God of the world and of all humanity.
The religion of Israel is not intended to be the religion of all humanity. Nowhere in the narrative does God imply that He wants the Egyptians to adopt Israelite religious practices. The point is quite different. Religion is particular. Morality is universal. If the story of the “heavying” of Pharaoh’s heart does allude to the Book of the Dead, then the story of the Exodus is not simply a partisan account from an Israelite point of view. It is telling us that certain things are wrong, whoever does them and whoever they are done against. They are wrong by Egyptian standards too. That was true of Pharaoh’s decision to kill all male Israelite children. That was an unforgivable sin against Ma’at.
Justice is universal. That is the point made plainly by the Torah’s three stories of Moses’ early life. He sees an Egyptian hitting an Israelite and intervenes. He sees Israelites hitting one another and intervenes. He sees Gentile shepherds behaving roughly to Jethro’s daughters and intervenes. The first was a case of non-Israelite against Israelite, the second was Israelite against Israelite, the third was non-Israelite against non-Israelite. This is the simplest way of telling us that Moses’ sense of justice was impartial and universal.
Finally, and most deeply, the Torah is hinting at a self-contradiction at the heart of the Egyptian concept of Ma’at. The most generous interpretation of Pharaoh’s refusal to let the people go is that he was charged with maintaining order in the Empire. A successful minority like the Israelites could be seen as a threat to such order. If they stayed and thrived, they might take over the country as the Hyksos had done several centuries earlier. If they were allowed to leave, other enslaved groups might be tempted to do likewise. Emigration is a bad sign when the place people are trying to leave is a superpower. That is why, for many years, the Soviet Union forbade Jews to leave the country.
Pharaoh, in his repeated refusal to let the people go, doubtless justified his decision in each case on the grounds that he was securing Ma’at, order. Meanwhile however, with each plague the country was reduced to ever greater chaos. That is because oppressing people, which is what Pharaoh was doing, was a fundamental offence against Ma’at...
For the first five plagues, Pharaoh could tell himself that he was enduring minor inconvenience to protect a major principle. But as the plagues became more serious, reducing Egypt to chaos, Pharaoh’s room for manoeuvre grew ever less. Having five times said “No” to the Israelites, he could not now back down without making himself look ridiculous, forfeiting his authority and damaging his standing. Pharaoh was a prisoner of his own system, held captive by his own decisions.
Seeking to protect order, he created chaos. That is because the order he was seeking to protect was built on a foundation of injustice: the enslavement of the many for the benefit of the few. The more he tried to defend it, the heavier his heart grew.
k-b-d (Strong's 3513), to make heavy
Exodus:
7:14-Then the Lord said to Moses, “Pharaoh’s heart is hardened; he refuses to let the people go
8:15-But when Pharaoh saw that there was a respite, he hardened his heart and would not listen to them, as the Lord had said.
8:32-But Pharaoh hardened his heart this time also, and did not let the people go
9:7-And Pharaoh sent, and behold, not one of the livestock of Israel was dead. But the heart of Pharaoh was hardened, and he did not let the people go.
9:34-But when Pharaoh saw that the rain and the hail and the thunder had ceased, he sinned yet again and hardened his heart, he and his servants.
10:1-Then the Lord said to Moses, “Go in to Pharaoh, for I have hardened his heart and the heart of his servants, that I may show these signs of mine among them,
ch-z-k (Strong's 2388) to strengthen
Exodus:
4:21
7:13-Still Pharaoh’s heart was hardened, and he would not listen to them, as the Lord had said.
7:22-But the magicians of Egypt did the same by their secret arts. So Pharaoh’s heart remained hardened, and he would not listen to them, as the Lord had said.
8:19-Then the magicians said to Pharaoh, “This is the finger of God.” But Pharaoh’s heart was hardened, and he would not listen to them, as the Lord had said.
9:12-But the Lord hardened the heart of Pharaoh, and he did not listen to them, as the Lord had spoken to Moses.
9:35-So the heart of Pharaoh was hardened, and he did not let the people of Israel go, just as the Lord had spoken through Moses.
10:20-But the Lord hardened Pharaoh’s heart, and he did not let the people of Israel go.
10:27-But the Lord hardened Pharaoh’s heart, and he would not let them go.
11:10-Moses and Aaron did all these wonders before Pharaoh, and the Lord hardened Pharaoh’s heart, and he did not let the people of Israel go out of his land.
14:8-And the Lord hardened the heart of Pharaoh king of Egypt, and he pursued the people of Israel while the people of Israel were going out defiantly.
14:17-And I will harden the hearts of the Egyptians so that they shall go in after them, and I will get glory over Pharaoh and all his host, his chariots, and his horsemen.
k-sh-h (Strong's 7185) to be hard/severe/fierce
Exodus:
7:3-But I will harden Pharaoh’s heart, and though I multiply my signs and wonders in the land of Egypt
13:15-For when Pharaoh stubbornly refused to let us go, the Lord killed all the firstborn in the land of Egypt, both the firstborn of man and the firstborn of animals. Therefore I sacrifice to the Lord all the males that first open the womb, but all the firstborn of my sons I redeem.’
It seems to me from the different uses in these verses that Pharaoh "made his own heart heavy" in immorality, of his own free will, by choosing to disobey God and Moses' requests. God then "strengthens" Pharaoh's heart more times than not, so Pharaoh holds strong to his own choices and resolve, which in turn leads to the punishments upon Egypt. God did not turn Pharaoh evil in order to accomplish these plagues, but rather strengthened a characteristic already present in Pharaoh by his own corruption.