What is the significance of the dish that Yaakov was cooking?
Rashi (to 25:30); Targum Yonasan: His grandfather Avraham had just died, and Yaakov was cooking the first meal 1 (the Se'udas Havra'ah) for his father Yitzchak.
Malbim: It is the food for the household. Esav, the Bechor, should have cooked it; he did not want to, for he was Ish Sadeh.
Which traditionally consists of cooked eggs or lentils (refer to 25:29:2). Oznayim la'Torah - This meal must be cooked by a stranger. This explains why Yaakov - who would have otherwise been in Yeshiva learning Torah - was cooking, and not Rivkah. Malbim - Esav was not concerned to mourn his grandfather; he came from the field!
We find (25:34) that Yaakov was cooking lentils. What is the reason?
Rashi (to 25:30) #1: Lentils (and eggs) are round. They symbolize Aveilus, which is a wheel that goes around in the world. 1
Rashi (to 25:30) #2: Because, like lentils (and eggs), an Aveil has 'no mouth' - he may not speak [about matters that do not pertain to the Mes].
Rashi (to 25:30) writes: "Why lentils? They resemble a wheel (i.e. a circle); and mourning is a sphere that revolves in the world." But both birth and death are cycles; and if so, we should eat lentils to mark a birth as well?
Gur Aryeh (to 25:30): Although the spheres (Galgalim) generate both entering and leaving of existence (in the Maharal's terminology, Havayah and Hefsed); existence itself is not dependent on time; unlike death itself, which is. 1
Maharal (Chidushei Agados Vol. 3, p. 76, to Bava Basra 16b): A new existence, before it comes about, does not exist at all! We cannot say that it "revolves from one person to another."
Compare Maharal (Chidushei Agados to Bava Basra 16b; and Ohr Chadash, p. 61). Also note the common custom to eat round chickpeas (at a Shalom Zachar) to mark a birth as well. (CS)
Rashi (to 25:30) writes that Avraham died five years before he had been destined to. What is the reason?
Rashi (to 25:30): So that he should not see Esav his grandson going out to evil ways - and that would not conform to the ''good old age" (15:15) that HaSh-m had promised him. 1
Why does the Torah say that Esav was 'tired' (Ayef), and not 'hungry'?
Rashi: Because he was exhausted after murdering. 1
Targum Yonasan: He was exhausted after having committed five 2 sins on that day: (a) He worshipped Avodah-Zarah; 3 (b) He shed innocent blood; (c) He committed adultery with a betrothed girl; 4 (d) He denied Techiyas ha'Mesim; (e) He despised the Bechorah. 5
The first three of them were through action. The last two did not cause him to be tired; in fact, they had not yet occurred! (PF)
Bava Basra 16b substitutes "denying HaSh-m" in place of idolatry. Mishnas R. Aharon (Vol. 3, p. 179) - Really, Esav had great Emunah. He was greatly pained over losing the Berachos! Rather, he did not esteem HaSh-m enough to stand up against his desires.
Moshav Zekenim: Kidushin does not apply to Nochrim! Even so, such an act is disgraceful, just like despising the Bechorah, which is not an Aveirah.
Mishnas R. Aharon (Vol. 1, p. 219): Why does the Torah mention only despising the Bechorah? This was the basis of his ruin - spiritual matters were not important to him at all. He cared only for the present, and even this was only for lowly things.
The verse teaches us that Esav was weary (Ayef). What is the deeper meaning?
Maharal (Netzach Yisrael Ch. 15, p. 88): Esav sold his first-born status because of his physical desires. Physical desire is defined as trying to fill a lack or deficiency. 1
QUESTIONS ON RASHI
Rashi writes: "He was weary (Ayef) - from [having committed] murder." But the term "Ayef" can also mean hunger or thirst?
Gur Aryeh: Anyone might come home hungry from the field! The verse should have written, 'Esav came in 'Ayef' from the field.' Rather it writes, 'Esav came in from the field, and he was 'Ayef;'' i.e. for a separate reason - namely, that he had committed murder.
Rashi writes: "He was weary (Ayef) - from [having committed] murder." The Gemara (Bava Basra 16b) teaches that Esav committed five sins that day. What does this number symbolize?
Maharal (Chidushei Agados Vol. 3, p. 76, to Bava Basra 16b): Most sinners abandon HaSh-m in one specific matter, whereas Esav cut off all connections to Him. Esav sinned in five ways, corresponding to the five aspects of the Neshamah - Nefesh, Ru'ach, Neshamah, Chayah, and Yechidah. 1
Maharal (ibid.): In this way, Esav was the polar opposite of Yaakov, who was Tam (whole). Maharal further explains the specific order of the sins Esav committed.