Why the Primeval Serpent Was Struck With Leprosy for Slander

[(Leviticus 14:2:) THIS SHALL BE THE LAW OF THE LEPER.] And so too you find regarding the primeval serpent: because he spoke slander against his Creator, therefore he was stricken with leprosy. And what did he say? Rabbi Joshua ben Levi said (Genesis 3:5): "For God knows that on the day you eat of it [your eyes will be opened, and you will be like God, knowing good and evil]." He said to her: Every craftsman hates his fellow. And when He wished to create His world, He ate from this tree and created His world. You too eat from it, and you will be able to create like Him. The Holy One, blessed be He, said to him: You have spoken slander; your end is to be stricken. As it is said (Genesis 3:14): "And the LORD God said to the serpent [Because you have done this, cursed are you above all cattle…]." With what did He curse him? With leprosy. And "cursing" (arirah) is nothing other than leprosy, as it is said (Leviticus 13:51): "for it is a malignant leprosy (tzara'at mam'eret)." Rabbi Huna of Sha'av said [in the name of] Rabbi Joshua ben Levi: The scales (that is, the colorings) that are upon the serpent are his leprosy. And not only that, but all who have blemishes will be healed in the World to Come, yet the serpent will not be healed, as it is said (Genesis 3:14): "Cursed are you above all the beasts." What is "above all"? That all will be healed, but he will not be healed. The children of Adam will be healed, as it is said (Isaiah 35:5-6): "[Then the lame will leap like a deer…] Then the eyes of the blind will be opened… [then the lame will leap like a deer…]." And concerning beast and cattle it is written (Isaiah 65:25): "The wolf and the lamb will graze as one." But the serpent has no healing, as it is said (ibid.): "and dust will be the serpent's food." Rabbi Helbo said: Even if he eats all the delicacies of the world, he tastes them only as dust. And so too in the time to come: "and dust will be the serpent's food," for he is never healed, because he brought the creatures down to the dust. And what caused this for him? Because he spoke slander. Therefore, "THIS SHALL BE THE LAW OF THE LEPER." There are many laws (torot) in this book: "This is the law of the burnt offering" (Leviticus 6:2); [(Leviticus 7:1:) "This is the law of the guilt offering";] "This is the law of the sacrifice of peace offerings" (Leviticus 7:11). And here too I have set in order a law for the leper: "THIS SHALL BE THE LAW OF THE LEPER."