Throughout the episode of the Plagues and the Exodus, the concept of yad chazakah (“mighty hand”) recurs consistently. The explanation is that without proof of G-d's power, there is no way in which the Gentiles will understand the reality of His existence in the world. Nowhere in all the prophetic writings does G-d ever suggest that He will prove His existence to the nations in any way other than through His and His nation's strength. And since the purpose of the Exodus was that “Egypt shall know that I am Hashem”, He had to demonstrate His power.
[However], if the purpose of the plagues was to force Pharaoh, and Egypt, to know Hashem, then why did G-d “harden Pharaoh's heart”? Had He not done so, then perhaps Pharaoh would already have freed the Israelites after the Plague of blood. Certainly, after the Plague of hail when he already confessed, “Hashem is the righteous one, and I and my people are the wicked ones” (Exodus 9:27), Pharaoh would have released the Israelites, had G-d not hardened (i.e. strengthened) his heart – as the Torah testifies. The Sforno (on Exodus 7:3) provides a clear answer to this. He explains that Pharaoh probably would have released the Israelites far sooner – but this would have been done out of fear of the Plagues, rather than unconditional acceptance of G-d and His might. That is to say, he would have attributed the Plagues to Moses' unique witchcraft, or a thousand and one other factors – and would have released the Israelites purely in order to spare himself the terror of these dreaded Plagues. Had this happened, the entire purpose of the Plagues would have been lost. G-d therefore strengthened Pharaoh's heart, so that he would not release the Israelites merely out of fear of the Plagues. The Plagues' progression forced Pharaoh into ever-deepening realization that there could be no cause for these Plagues other than Hashem, the G-d of Israel – as Moses had said right from the start.
Rav Binyamin Ze'ev's father, Rabbi Meir Kahane, writes similarly on this in “The Jewish Idea”: Likewise, regarding the hail, it says (Ex. 9:14) “This time I am prepared to send all My plagues against your very heart. They will strike your officials and your people, so that you will know that there is none like Me in all the world.” [...] That is, they were to bring their livestock inside because of the hail. Indeed, “those of Pharaoh's subjects who feared G-d's word made their slaves and livestock flee indoors”(Ex.9:20) This was the first time G-d gave the Egyptians the chance to save themselves from a Plague. Why did He do so? Were they to heed G-d, it would constitute acknowledgment that indeed the L-rd is G-d and that He, alone, controls the laws of nature. This, in turn, would be the beginning of the collapse of his nation's abominable idolatry. The purpose of the plagues in Egypt was to sanctify G-d's name and to prove to the world that indeed Hashem is G-d, Omnipotent Creator of all. Pharaoh had shown G-d contempt by saying (Ex. 5:12), “Who is Hashem that I should hearken unto His voice to let Israel go? I know not Hashem.” Through the degradation and punishment of the idolatry of Egypt, Pharaoh was humiliated. Therefore, G-d warned the Egyptians that He was bringing the hail and that the princes and deities of Egypt would be unable to prevent it. The Egyptians would be saved only if they abandoned their faith in their abominations and subjected themselves to G-d through belief in Him, expressed by making their servants and flocks flee into the houses. Through this, their faith in idolatry would be destroyed and G-d's name sanctified, the whole purpose of the Plagues.
“With a mighty hand”. G-d had to direct His strength against the Jews, too in order to bring them out, for they did not want to leave. As Chazal[our sages of blessed memory] say, four-fifths of the Israelites died in the Plague of darkness. But even those who did eventually leave, did so unwillingly: G-d said, “For with a mighty hand shall he [Pharaoh] send them away, and with a mighty hand shall he expel them from his land.” Chazal's commentary on the verse, “They did not listen to Moses, due to anguish of spirit and hard labor” (Ex. 6:9), is truly astounding: Is there any man who receives good tidings and does not rejoice?...But they found it hard to abandon idol worship. (Mechilta, Pis'cha 5, end of first paragraph) That is, they were willing to remain in the dungeon of slavery and oppression, in order not to accept upon themselves the yoke of Heaven – that yoke which liberates man from the shackles of animalism, freeing him from bondage to those passions that dominate him. And when the children of Israel complained in the wilderness: ”We remember the fish that we ate in Egypt free” (Num. 11:5), Rashi says there: “Free from the commandments”. The truth is that the Jews were never ready to leave exile of their own free will, and when they were able to assimilate, they did. But all these attempts were to no avail. On the contrary – precisely when the Jews tried to be accepted by Gentile society by blurring their unique, separate identity, the hatred towards them only increased. Such was the case in Egypt, as the Psalmist said: ”He turned their [the Egyptians'] hearts to hate His people, to conspire against His servants. (Psalms 105:25). So too has it been throughout the generations. And even those who do eventually leave, do so only out of necessity. Slavery, pogroms and holocausts force some of them to realize, albeit grudgingly, that there is nothing for them there – and then they ascend to the Land of Israel, as witnessed in our generation. Chazal identified this mind-set in the following words: “Among the nations you will not know peace and you will not find rest for your feet” (Deut. 28:65) – had Israel found peace, they would not have returned. (Genesis Rabbah 33:6) That is to say, if the Jews will not return to the Land of Israel willingly, then G-d will inflict such troubles on them, that they will be forced to return. And in our days, in spite of all that has happened, most Jews have not learned the lesson.
“And Hashem our G-d brought us out of Egypt with a mighty hand” (Deut 6:21). Since G-d secretly weeps over the lost pride of Israel, He therefore yearns to redeem them both from the actual place, as well as from the mentality of exile. Had Pharaoh given them better economic conditions, eased their enslavement slightly, flashed an occasional smile at them or the merest nod of encouragement – then they would have felt a debt of gratitude to him. Out of respect for him, they would willfully have submitted themselves to slavery, and all future generations would have effaced themselves at the mere mention of Pharaoh's name. The physical and spiritual enslavement would have been worse – our forefathers would never had left the exile of their own free will, and the exile mentality would never have left them.” (Mishna Yeshara of Rav Binyamin Ze'ev Kahane's grandfather, Rabbi Yechezkel Shraga Kahane).
Israel's redemption is not merely the story of one more people's national liberation. Israel's Exodus from Egypt ushered in a new era – a divine nation was established, as well as a purpose for the world. The mission of this liberated nation is Kiddush Hashem, and the erasing of the heresy of chillul Hashem, of [Pharaoh's words] I do not know Hashem. Therefore, had Hashem Himself not brought our forefathers out of Egypt with this intention, then even had a good king freed them, it would have been meaningless, because it would not have led to the establishment of that divine nation, and the fulfillment of its glorious destiny.
The Exodus had to be implemented, directly and unequivocally, by G-d and not through any agent, because the battle here is a paradigm of all subsequent history, the basis for Israel's faith throughout their generations – the knowledge of Hashem, versus “I do not know Hashem”. It is concerning this struggle that G-d promises, “I will execute judgement against all the gods of Egypt.”
This is a religious war: the G-d of Israel versus the gods of the nations [and, one has to add, against Israel's trust in the nations!] Just as Israel was redeemed from Egypt without having to turn to any outside party or human ally (which was precisely what the Egyptians originally feared : “If war breaks out, they will join our enemies, fight against us, and leave the country”[Ex. 1:10]), so must we understand that in our generation, too, G-d is Israel's sole Redeemer – not Lord Arthur Balfour, not the United Nations, not the U.S.A.
Compiled by Tzipora Liron-Pinner from "The Haggadah of the Jewish Idea" and "The writings of Rav Binyamin Ze'ev Kahane; HY"D " and from "The Jewish Idea" of Rav Meir Kahane