In פרשת תולדות (Gen. 25:19 to 28:9) both Isaac and Jacob receive blessings. Although in both instances others call their deservingness into question, the Torah suggests that the blessings are neither arbitrary nor unconditional, but tied to the fulfillment of spiritual responsibilities.
Despite a famine in Canaan, Hashem tells Isaac: "Sojourn in this land and I will be with you and bless you; for to you and to your offspring will I give all these lands, and I will establish the oath that I swore to Abraham your father: 'I will increase your offspring like the stars of the heavens; and will give to your offspring all these lands'; and all the nations of the earth shall bless themselves by your offspring" (Gen. 26:2-4). The blessing includes both possession of the Land and fertility for Abraham and his descendants. Moreover, the fertility seems to extend to the land as well. "Isaac sowed in that land, and in that year he reaped a hundredfold" (Gen. 26:12-14). While this blessing may seem to be unconditional, a closer reading suggests it is tied to spiritual responsibilities. Hashem prefaces the blessing by telling Isaac, "Do not descend to Egypt" (Gen. 26:2). This warning carries a symbolic meaning as well as a literal meaning, i.e., do not descend spiritually to Egypt and all it represents. Hashem also reminds Isaac of his spiritual responsibilities at the end of the blessing: "Because Abraham obeyed My voice, and observed My safeguards, My commandments, My edicts, and My Torahs" (Gen. 26: 5).
The Philistines are envious of the blessing bestowed upon Isaac (Gen. 26:14). They also dwell in the Land, but--as evidenced by the famine--it doesn't bloom for them the way it does for him. Moreover, they see Isaac's prosperity as both a threat and a usurpation. Abimelech, the Philistine king, tells Isaac: לך מעמנו כי–עצמת ממנו מאר (Gen. 26:16). He expels Isaac ("go away from us"), and in Hebrew the reason for the expulsion can be rendered in two ways: "because you have become mightier than us" or "because you have become mighty from us." The first reading indicates fear of Isaac's power, the second the notion that Isaac has dispossessed the Philistines of what is rightfully theirs.
The Torah suggests that if the Land blooms for Isaac and not for the Philistines, it is because Isaac has shown himself to be spiritually fit. In contrast to the Philistines, who make the land desolate by stopping up the wells that Abraham dug in the Negev desert, Isaac re-digs them (Gen. 26:15-18). If the well symbolizes the womb and if (as Nehama Leibowitz says) "water means life," then to stop up the wells is to stifle fertility. (The fact that Isaac is redigging his father's wells suggests an additional Freudian interpretation, but I'll leave that aside for now.) Moreover, according to some readings, re-digging the wells is not only an act of physical reclamation but a fulfillment of spiritual responsibilities as well. One rabbinical commentator emphasizes that Isaac called the wells "by the same names that his father had called them" (Gen. 26:18). Like Abraham, Isaac called the wells "by the name of the Lord" to remind all who used the wells that Hashem was the source of the water and thus of life and thus of blessings. In this way, both Abraham and Isaac were public educators who used the wells for pedagogical purposes. In contrast, according to this midrash, the Philistines "reverted to idolatry" after Abraham's death "and in order to erase from their memory the names of these wells, which recalled the very opposite of their false opinions, they stopped up the wells."
We find a parallel in the story of Isaac's sons, Jacob and Esau. Just as Isaac appeared to the Philistines as an illegitimate usurper and dispossesser, so Jacob appears to Esau when he acquires his older brother's birthright for a mess of pottage (Gen. 25:29-34) and, by means of trickery and deception, their father's blessing (Gen. 27:1-40). In fact, the Hebrew root (עקב) of Jacob's name (יעקב) means "to overreach" or "to supplant."
But here too the Torah suggests that Jacob's usurpation is only apparent. If Jacob receives the blessing, it is because his brother Esau shows himself to be spiritually unfit. Esau married two Hittite women, who "were a provocation of the spirit to Isaac and Rebecca" (Gen. 26:34). Rashi comments: "All of the actions of [Esau's wives] were a cause of anguish to Isaac and Rebecca because they worshipped idols." According to the Talmud, Esau himself became an idolator, presumably through the influence of his wives. Rather than teaching them the ways of Hashem, as Abraham and Isaac endeavored to do with the wells, Esau learns their idolatrous ways. For this reason Rebecca tells Isaac "I am disgusted with my life on account of the daughters of Heth" (i.e., the Hittite daughters-in-law) and why they take great pains to ensure that Jacob will not follow in his older brother's footsteps (Gen. 27:46, 28:1-8). What's more, when Esau complains to his father that Jacob deprived him of the paternal blessing that Esau expected, Isaac answers him this way: "Your brother you shall serve; yet it shall be that when you will be aggrieved, you may remove his yoke from upon your neck" (Gen. 27:40). What Isaac means, Rashi explains, is that "when Israel will transgress the Torah, and you will have a claim to be aggrieved over the blessings that [Jacob] took, 'You may remove his yoke, etc.'" Once again, we find that blessings come with spiritual responsibilities and depend upon their fulfillment.
