Jacob departed for Laban’s house with dual roles, much like Eliezer. His first was to seek a wife for himself. His second was to represent Isaac, whose paternal role obligated him to seek, on behalf of his son, a wife who would facilitate Jacob being entrusted with Abraham’s tradition. The Torah repeats that Isaac granted Abraham’s blessing to Jacob before sending him to Padan Aram, to emphasize that Jacob was also acting as Isaac’s emissary, to find himself a proper wife, one that would satisfy the pre-requisite to receiving the blessing.
After Abraham verified that Rebecca was indeed a worthy wife for Isaac, the Torah says, “vayiten Avraham lYitzchak,” Abraham transferred the tradition to Isaac. However, Isaac realized that he might never meet Jacob’s spouse. Perhaps she would not be suitable for her role and Jacob would not merit inheriting Abraham’s blessing. Isaac says, “vyiten lcha,” G-d should give you Abraham’s blessing in the future, on the condition that you fulfill your mission of marrying a wife suitable to carry on Abraham’s tradition.
Why does the Torah interrupt Jacob’s story to mention Esau’s marriage to Ishamel’s daughter? At the age of 40, Esau married two Hittite women who made life miserable for Rebecca and Isaac. Presumably, they were the impetus for Rebecca’s diatribe against the local Hittite women, as well as her insistence that Jacob seek his wife elsewhere. Esau attempted to prove to his parents that he too could select a non-Hittite wife from Abraham’s household, Ishmael’s daughter. The Torah contrasts Jacob’s departure to seek an appropriate wife, with Esau’s feckless attempt to deceive his parents by adding another wife to his collection of deviant women, clearly demonstrating that he was not worthy of receiving Abraham’s blessing or tradition.