We will now introduce fascinating but disturbing teachings related to this subject from the Zohar hakadosh (ibid.). The guardian angel of Eisav is none other than the “nachash hakadmoni” who caused Adam and Chava to sin with the Eitz HaDa’as and was punished by having its legs cut off. This motivated it to wrestle with Yaakov Avinu and strike a blow to the ball of his thighbone—i.e., those who support Torah-study. They represent the legs of kedushah; when they are not supporting Torah-study, the “nachash hakadmoni” commandeers those legs enabling it to stand and walk on them to combat the legions of kedushah.
How sweet are the words of the great Rabbi Aryeh Leib Tzintz of Platsk in Derashos Harael (Part 3, Drush 23). He explains the deeper message of the passuk (Iyov 1, 6): "ויהי היום ויבואו בני האלהים להתייצב על ה' ויבוא גם השטן בתוכם, ויאמר ה' אל השטן מאין תבוא, ויען השטן את ה' ויאמר משוט בארץ ומהתהלך בה." It happened one day; the angels came to stand before Hashem, and the Satan, too, came among them. Hashem said to the Satan, “Where have you come from?” The Satan responded to Hashem and said, “From wandering about the earth and walking on it.” Rashi explains that the Satan told Hashem that it is his modus operandi to wander about and observe the bad people and the good people. The redundant language of the passuk--“from wandering about the earth and walking on it”—needs to be explained.
The explanation, however, is that this is the Satan’s method of finding fault with Yisrael. When he wishes to wander among G-d’s creatures to check if they are meritorious or not, he must do so on his belly, since he lacks legs to walk around on. If, however, he finds that Yisrael, chas v’shalom, are not studying Torah properly—due to a failure on the part of the benefactors of Torah-study—known as “Yaakov’s legs”—to fulfill their commitment, the Satan steals those legs for his own needs to actually walk around on earth.
So, when HKB”H inquires of the Satan, “Where have you come from?” His respon se constitutes an indictment against Yisrael: “From wandering about the earth and walking on it.” At first, I wandered about the earth, crawling without legs, to see if the people were meritorious or not; however, once I did my due diligence and found that they did not support Torah-study as they should, I was no longer restricted to “wandering about the earth” on my belly—but, instead, I was also able to “walk on it.” This was because I succeeded in confiscating “Yaakov’s legs,” which were remiss in their support of Torah-study; this enabled me to use them for my own needs and walk on them.
