출애굽기 10:1의 미드라쉬

(Exod. 10:21:) THEN THE LORD SAID UNTO MOSES: STRETCH OUT YOUR HAND TOWARD THE HEAVENS <THAT THERE MAY BE DARKNESS OVER THE LAND OF EGYPT>….¹Note that both Tanhumas seem to omit the beginning section (Exod. 10:1–20) of parashah Bo. The missing passage seems to include a whole parashah of the so-called triennial cycle. This text is related (to Ps. 105:28): HE SENT DARKNESS, AND IT BECAME DARK; [FOR THEY DID NOT DEFY (maru) HIS WORD]. The darkness which the Holy One sent upon Egypt was very severe. R. Aha said: <It was> because they did not accept the {regulations middotaw} [authority (marut)] of the Holy One over themselves.²By interpreting the verb maru as coming from the same root as the word for authority, R. Aha has interpreted the second part of Ps. 105:28 to mean: FOR THEY DID NOT ACCEPT THE AUTHORITY OF HIS WORD. Similarly Tanh., Exod. 3:1; Exod. R. 14:1; M. Pss. 105:9. Our Masters have said: What is the meaning of THEY DID NOT DEFY (MRH) HIS WORD? <It is> in reference to their having disregarded (rt.: MRH) the word of the Holy One. The Holy One said to the ministering angels: The Egyptians deserved to be smitten with darkness. Immediately they agreed and said: Yes. Not one of them rebelled (rt.: MRH) against the Holy One. (Ps. 105:28b:) THEY DID NOT DEFY (MRH) HIS WORD. (Vs. 28a:) HE SENT DARKNESS, AND IT BECAME DARK. To what is the matter comparable? To a king whose servant sinned against him. So he said to someone: Go and give him fifty lashes. He went and gave him a hundred. Thus he increased <the punishment > on his own. So did the Holy One send darkness over Egypt, and the darkness increased. (Ibid.:) HE SENT DARKNESS, AND IT BECAME <even more> DARK.

Another explanation: For I have hardened his heart - Rabbi Yochanan said: Does this not provide heretics with an opportunity to open their mouths to say that he had no means of repenting, as it say "For I have hardened his heart". Rabbi Shimon ben Lakish said to him: Let the mouths of the heretics be stopped up. Rather, (Mishlei 3:34) If it concerns the scorners, he scorns them. When the Holy One Blessed be He warns a man once, twice, thrice and he doesn't repent, and G-d will close his heart against repentance so that He should not exact vengeance from him for his sins. So to with the wicked Pharaoh, since Hashem sent five times to him and he took no notice, G-d then said: "You have stiffened your neck and hardened your heart; well, I will add impurity to your impurity". Hence, "For I have hardened his heart". What does "I have hardened" imply? That G-d made his heart like a liver (כבד) into which even if boiled a second time no juice enters; so also was the heart of Pharaoh made like a liver, and he did not receive the words of G-d. Hence, "For I have hardened his heart".