Musar על מכות 19:20

Esau ridiculed this, saying that Adam had been able to reproduce other human beings of whom the Torah testifies that they were "in His image and form," i.e. of equal or greater worth. Thereby he had restored the damage Cain had wrought (Genesis 5,3). This occurred when Shet was born, who provided the strain of mankind that survived the deluge. Esau vowed not to repeat Cain's mistake, but to ensure that no one could be sired by Isaac to replace Jacob. He particularly wanted to destroy one of the pillars supporting the universe, i.e. the Torah, which was represented by Jacob, the יושב אוהלים, the dweller in tents (a euphemism for Torah academies). On Genesis 25, 27, Rashi explains the plural as comprising the academies of Shem and Ever respectively. Esau reasoned that during the days of mourning for their father Isaac Jacob would have to interrupt his Torah study and the angel of death, Esau's guardian angel, would be able to claim him at such a time. We know from king David that the angel of death could not touch David while he was immersed in Torah study. He had to be distracted so that the angel of death could claim his soul. The Talmud relates a similar occasion when the angel of death tried to claim the soul of Rabbah. The latter had to be distracted through some tremendous noise (Baba Metzia 86).