Essentially, the central theme of this parsha is the quest of Yaakov and Eisav for their father’s blessing. A superficial reading of the parsha suggests that Yitzchak and Rivkah each had personal reasons for favoring one twin over the other and that there was a communication problem in their home. After studying the various commentaries, one learns that this was clearly not the case.
In response to the obvious question, why was Yitzchak so insistent on blessing Eisav, the Radak explains that Yitzchak was acutely aware of Eisav’s character traits. His evil behavior and rebellious, antagonistic attitude had not escaped Yitzchak’s attention. Indeed, he sincerely hoped that by blessing Eisav, he would inspire him to repent.
Horav Gedalya Schorr z.l. offers a novel approach to this question. He cites the Arizal, who interprets uhpc shm hf as meaning more than the literal translation implies. Yitzchak was not impressed by the piece of venison. The Midrash explains that Eisav fooled Yitzchak with his “mouth” by asking profound questions pertaining to halachic matters. The Arizal asserts that Eisav did have within himself sparks of kedushah, holiness. These sparks emanated through his mouth, reflected by the questions he asked. He demonstrated to Yitzchak that he still possessed some hope for spiritual development. Yitzchak loved him for this attribute. Thus, he sought to help Eisav overcome his impediments to spiritual ascendency by offering him the blessings.
Horav Schorr develops his theme further by applying the words of the Ramban in Parashas Eikev. The Ramban relates that every bracha, blessing, found in the Torah is an expression of support for the individual who was blessed. A bracha offers an individual the determination that conditions during his lifetime will enhance his ability to serve the Almighty to his highest potential. Eisav was in dire need of such circumstances since his nature and personality were counterproductive to the ideals which his father expected him to develop.
Yaakov, on the other hand, was an “ish tam,” a complete perfect person whose life of virtue, determination, and erudition created the optimal circumstances for his spiritual growth. One who is not compelled to challenge evil does not need blessing, only encouragement. One whose essence is evil must have blessing in order to overcome his challenge.
Rivkah was raised in a home replete with iniquity. She was exposed to the wicked Besuel and the unscrupulous Lavan. Therefore, she was more sensitive to the real nature of Eisav. True, he had sparks of kedushah which emanated from his mouth. They were only a superficial facade, however, which had no relationship whatsoever to his essence. Indeed, Eisav’s most notable sign of impurity was his desire to demonstrate his virtue. When Rivkah saw that Eisav had no desire for spiritual development, when she noticed him ridiculing everything which Yitzchak represented, she determined that this child was not entitled to blessing. Only Yaakov, who she felt would take these blessings and apply them to a life of Torah and mitzvos, should be the recipient.