In follow-up to the previous (Yom Shishi) post...
Commenter: "...there's also a good part of Esav. That's not my opinion, but what the sages say."
I would really love to see where the sages say that. Til now, I just haven't seen it - anywhere. In fact, what I read in the commentaries seems to indicate just the opposite:
...All character traits, even the basest, can be used for good. Man must harness his nature and not let his nature harness him. David and Esau had similar personalities, but David utilized it for good and became one of the greatest people who ever lived. Esau let his nature run rampant, and became the eternal symbol of evil and cruelty.
Until they grew up - i.e. reached bar-mitzvah age - they were relatively similar to one another and Esau's pranks were attributed to childishness (Sifsei Chachamim). From the age of thirteen, the essential differences became apparent, with Esau turning to idols and Jacob going to the study hall. Esau became a hunter, but not only in the literal sense. He became adept at trapping his father by asking questions that would make him appear to be unusually pious.... Jacob, however, was morally wholesome, saying what he thought and never being duplicitous, and spending all his time in the study tents of Shem and Eber (Rashi).
God's blessing to Abraham specified that only one of Isaac's children would be heir to the mission of Israel (see Rambam, Hilchot Melachim 10:7), meaning that the Torah would go to Jacob or Esau, but not to both.
[This would seem to negate the idea of Esau being a "fourth avot."]
Rashi cites the Midrash: Esau is compared to a swine that, when it lies down, stretches out its cloven hoof, as if to say, "See, I am a kosher animal!" Similarly, the princes of Esau rob and extort while they pretend to be honorable....So it was with Esau. Until he was forty, he had been living immorally, enticing married women from their husbands, but when he became forty, he said hypocritically that he would follow the example of his father who married at that age.
Unlike his father, however, Esau married Hittite women; his passions were unbridled and he chose to marry into a nation that matched his evil nature. With these marriages, Esau set the seal on his complete unfitness to carry on the mission of Abraham..... (R' Hirsch)
...[Isaac] felt, according to some, that the two brothers should both be parts of God's nation: Jacob with the higher calling of Torah scholarship and spiritual ascendancy, and Esau with material success that he would use to support and assist Jacob. Had Esau been worthy, this could have happened,.... Rebecca, however, guided by Divine inspiration, knew that Esau was not entitled even to this.
...Having been told before the twins were botn that the younger would be the superior one, Rebecca knew that the blessings had to go to Jacob. She also knew from that prophecy that the two could not coexist - because when one would rise the other would fall - so that any plan Isaac might have to enlist them in joint service of God could not succeed - but she had not been commanded to convey this knowledge to Isaac....
[When it says "Isaac trembled...", v. 27:33] Isaac perceived that Gehinnom opened beneath Esau (Rashi), which was in sharp contrast to the fragrance of Eden that had accompanied Jacob in Isaac's chamber.
The presence of Gehinnom with Esau made Isaac realize that he had been deceived all along - Esau was truly evil. This made Isaac fear that the vision of Gehinnom proved that he, Isaac, would be punished for having allowed himself to be so grievously misled (Pesikta d'Rav Kahana).
["...Rebecca, mother of Jacob and Esau." v.28:5] The verse repeats the obvious to imply that even though Esau had the same genealogy as Jacob and it would have been just as logical for his parents to ask him to seek his mate in Haran, they did not do so because the heir of Abraham was Jacob, not Esau (Ramban).
The passage [describing Esau's marriage to the daughter of Ishmael] justifies the portrait of Esau as a selfish person, oblivious to all but his own desires. For twenty-three years he had permitted the behavior of his Canaanite wives to cause anguish to his parents, yet it seems to have dawned on him only now. Instead of divorcing them, however, he merely took another unsuitable wife in addition to them. Thus he proved that he had no feeling for the House of Abraham, and Rebecca's assessment of his complete unfitness for the future leadership of the nation was fully justified (R' Hirsch). (Source: Stone Edition Chumash commentary)In other words, Esau did not repent in his lifetime and his descendants have followed in his path for these 4000 years. In fact, we are told that the Torah was offered to them before it was offered to us and they rejected it...
...the Holy One blessed be He offered the Torah to every nation and every tongue, but none accepted it, until He came to Israel who received it!" (Avodah Zara 2b). ... It was not G-d who chose Israel, it was the other nations that refused to accept the Torah when it was presented to them. This rejection is explained in part by the prohibitions that those nations were unable to accept - for murder is endemic to the children of Esau, adultery to the children of Ammon and Moab, and theft to the descendants of Ishmael, and "they were unable to accept even the seven commandments accepted by Bnei Noah and threw them off". (Sifre Devarim 343).But, as is well known, any gentile from among these nations who wants to accept the Torah, can do so by conversion. And any gentile who wants to better himself without converting is only obligated to the Sheva Mitzvot Bnei Noach; however, they are then considered as attached to the Jewish nation rather than remaining part of Esau, etc.