What did Isaac do? He grasped the head of Esau and prayed before the Holy One, blessed be He, and said: Sovereign of all the universe! Let mercy be shown to this wicked one, for he had not learnt all the precepts of the Torah, as it is said, "Let favour be shewed to the wicked, yet will he not learn righteousness" (Isa. 26:10). He was speaking in iniquity concerning the land of Israel and the Cave of Machpelah, as it is said, "In the land of uprightness will he deal wrongfully" (ibid.).
The Holy Spirit answered him, saying: As I live! he shall not see the majesty of God.