Musar sobre Gênesis 2:6

The Priest next makes her swear the שבועת האלה, "the curse of adjuration," that same curse stemming from his original encounter with the serpent. When G–d fashioned man, He took from the dust around the earthen altar, and thus vapor rose to irrigate that dust, so that man was formed from dust and water. When man became corrupt and sinned, he became a vessel made of earthenware on account of this dust contained in the material he was made of. The water that was also part of him, made him liable to impurity, since we have a halachic rule that water makes something capable of becoming impure in the first degree, ראשון לטומאה. This is why the סוטה is given water to drink out of a vessel made of earthenware.

The Tziyoni writes in a gloss on פרשת בראשית that the reason we are to be so careful with observing the details of the legislation of צרעת, blemishes of the skin, the clothes, or the house, is that we are dealing here with inner blemishes, i.e. sins, which have become visible externally. G–d has been very kind in externalizing the effect of these sins so as to give the afflicted person an opportunity to repent and rid himself of the pollutant of the serpent which his sins are due to. The priest is the only one who can effect a cure because the priesthood originated in the "right" side of the diagram of emanations in the emanation חסד, whereas the pollutant of the serpent has its origin in the "left" of the diagram of emanations, the side from which Samael originates. Nowadays, when we do not have priests who can perform the steps leading to the rehabilitation of an afflicted person (including the sacrifices he has to bring at the end of the period of his isolation as outlined in Leviticus 14,2-32), repentance is the only instrument by which we can cleanse ourselves. The right hand of G–d is always stretched out to welcome penitent sinners.

What all this has to do with Samael injuring the כף ירך יעקב, the thigh joint of Jacob, is simple. Our sages say on 32,26: וירא כי לא יוכל לו, ויגע בכף ירכו ותקע כך ירך יעקב, that the thigh joint of Jacob refers to the later descendants who experienced the harsh decrees by the various nations who were their hosts in exile. When the Hasmoneans overcame the Greeks, they reversed this injury, i.e. the כף became a פך a cruse of oil. What had been a vulnerable part of Jacob's ירך now became the solid basis of the candelabra, ירך מנורה.