Dual natured Yaakov

When Itzchak wants to give Esav his blessing is he intending to continue God's choosing process? If so why wouldn't he recognize the spiritual one, God's choice? What would give him the audacity to continue what only God had done up to this point?

It seems logical that Itzchak understood that at some point a whole family had to be chosen in order to become a nation and since both his children came from the same mother Rivka, in fact they were twins, both sons would carry on the chosen(bechira) line. As opposed to the two sons of Avraham with whom only one was chosen by God as Avraham was.

Itzchak understood God's choosing process. He believed that his two sons were bechira-chosen to propagate the nation. He did not receive the prophecy that Rivka had and apparently Rivka didn't tell him. Esav was "a man of the field". A man of physicality in charge of the physical needs of the family-food, protection, business, etc. He would be naturaly the king of the clan. The blessing(beracha) that Itzchak intends to bestow on him has very similar elements to the blessings that Yaakov later bestows on Yehuda and Yoseph(Bereishis49:8, 22ff) who at the time were present and future leaders/kings.

Yaakov's blessing is a bit more complicated but there are some similarities with the levitical roll (Devarim 33:10) and some similar word usages that Yaakov later says to Shimon and Levy in his blessing/curse to them such as congregation(Bereishis 49:5). Although Itzchak gives a Birchos Avrahom he does not grant him bechira but says, "May He grant you the blessing of Avraham". Perhaps at this point Itzchak is now beginning to understand what Rivka has known all along that the two sons are two nations.

So Yaakov is the natural spiritual leader. He is a man "abiding in tents". He represented the priesthood, Torah study-the clergy. Now that he stole Esav's blessing he has to become dual natured-a man of the field and a man who abides in tents. King and Priest. When he is complete it is his progeny that become the bechira nation.