What was the nature of Esav's argument?
Rashi (to Sanhedrin 101b): Esav's argument was irrefutable (surely you have a Berachah left for me)!
Torah Temimah: The Gemara (Sanhedrin 101b) says that it was "ba'Alilah," i.e. libelous or false. He knew that Yitzchak had already given everything to Yaakov!
Malbim: You say that my Berachah was only to support Yaakov. I do not desire this. I want wealth and authority for my own benefit in this world, and not for the sake of the world to come!
Ha'amek Davar: [Even if you made him master over me,] you can bless also me with grain and wine!
What did Esav's crying achieve?
Rashi (to Tehilim 80:6): The Pasuk "va'Tashkeimo bi'Dema'os Shalish" (Tehilim 80:6) alludes to "Tze'akah Gedolah u'Marah" (in our Pasuk), the three tears that Esav shed 1 at losing his father's blessing. On that merit, he was given the blessing of 'living by the sword.'
Eliyahu Rabah (22): As a reward for two tears, he was given Har Se'ir, from which rain of Berachah never ceases. 3
Refer to 27:39:152:1.
As Chazal say (in Berachos 32b), 'The gates of tears are never shut!'
Lev Eliyahu (Bereishis, p. 85): The Midrash equates them. Esav's pain over losing the Bechorah and Berachos equaled Mordechai's pain over the decree to kill all the Yehudim. Esav knew the eternal value of what he traded for a fleeting pleasure - just he followed his heart's desire.
Mishnas R. Aharon (Vol. 1, p. 219): Perhaps this was due to his Emunah, which was expressed through his pain (over the loss of the Berachos).
QUESTIONS ON RASHI
Rashi writes: "'Ha'Veracha Achas' - The letter Hey expresses astonishment, as in the verses...." What is Rashi trying to prove with the verses he cites?
Gur Aryeh: Usually, a Hey that indicates a question or astonishment is vowelized with a Sheva (i.e. a Chataf-Patach); whereas in this word, the Hey has a Patach. 1 Rashi cites additional examples where this is the case; and the reason is that the following letter also has a Sheva, and two Shevas cannot come consecutively. 2