A short but extremely deep thought on Parshas Toldos.
Obvious question: Why did Yitzchok intend to give the Brochos to Esav and not to Yakov.
Answer: There were two Brochos. One of Rulership, intended for Esav. One of the Mesorah, the Birchas Avrohom, given to Yakov before he left to Choron.
True rulership begins at home. Only someone with a powerful Yetzer Hora can experience true rulership. In a deeper sense, the term melech refers to a king that is chosen, as opposed to a Moshel, a dictator. It is the Yetzer Hora, who forces us to choose our relationship with G-d, as opposed to naturaly following Him.
The stronger the Yetzer Hora, the greater of a choice we have, the greater meaning we give to G-d’s rulership upon his being vanquished.
The point of a Jewish king is to reflect the Divine rulership in this world.
Dovid Hamelech ultimately accomplished what Esav was supposed to have done. He was endowed with a mighty Yetzer Hora, which he overcame with unparalleled effort.
Yitzchok knew that only Esav had in his lot this necessary prerequisite to rulership. He was right. However, by receiving Esav’s Brocha in his stead, Yakov absorbed Esav’s lot in addition to his own. His subsequent sojourn to Charan, to face the unprecedented exposure to the house of Lavan, forced him to combat evil in a manner previously unknown to him.
When people said the big (Leah) for the big (Esav) they were correct. The Medrash Rabbah says that she, who containes the seeds of Davidic rulership, was predestined for Esav. Yakov, with his newfound role ultimately took even her.
Bottom line. Every urge of the Yetzer Hora that we experience is an opportunity for true expression of Divine Rulership.