What "Avon Avosav" should be remembered?
Rashi: It is the Aveirah that he ruined his fathers - [Esav] caused Avraham to lose five years of his life (he died early, lest he see Esav depart from the Torah way) and caused his father's eyes to become weak (so Yakov could get the Brachos 1 ).
Radak: "Poked Avon Avos Al Banim" (Shemos 20:5).
Malbim: His father's sins should be remembered, so the entire family will be cut off. Up to here is what David's enemies cursed him. After this, their curses are returned onto them.
Esav is blamed for this, for had he been worthy, there would be no need to give the Brachos to Yakov! (PF)
What is "Chatas Imo"?
Rashi: He ruined her womb, and caused the day of her death to be hidden from people, lest they curse her, for Esav left her stomach. It says "va'Tamas Devorah Meinekes Rivka... Alon Bachus" (Bereishis 35:8) - in Greek, 'another' is called 'Alon'. Yakov had another Aveilus together with that over Devorah. His mother died, and the Torah covered it up.
Radak: His mother's sin (should not be erased; it should be remembered for her son).
