Seder Toldot
v'eileh toldot yitzhaq ben avraham avraham holid et yitzhaq (And these are the descendants of Isaac, Abraham's son. Abraham fathered Isaac) (Genesis 25:19)
The Midrash Rabbah (Genesis 63) says:
It is written (Proverbs 23:24): "the father of the righteous will greatly rejoice and he who begets a wise child will be glad in him (gil yagil avi tzadiq v'yoleid hakham yismah bo)." There is rejoicing after rejoicing when a righteous child is born (gilah ahar gilah bi-z'man she-ha-tzadiq nolad).
It appears to our master to say that the term "righteous" (tzadiq) here refers to one who was righteous from birth. A child can be righteous from birth only by virtue of the holiness of his parents. The term "wise child" (hakham) refers to one who has elevated himself through his own knowledge and intellect, not by virtue of his genetic makeup. That is why Noah was called "righteous" (tzadiq) and Avraham "wise" (hakham) as explained elsewhere (see Seder Noah v'noah ish tzadiq tamim hayah b'dorotav). Now the Sages deduced from the passage "and the Lord listened to his prayer" (va-yei'ater lo), which implies that G-d listened only to Yitzhak's prayer, not to Rivkah's, that the prayer of a righteous person who is the child of a righteous person (tzadiq ben tzadiq) is preferred to that of a righteous person who is the child of a wicked person (tzadiq ben rasha). The Scripture, therefore, says "Abraham fathered Isaac" (Avraham holid et Yitzhaq), inasmuch as Yitzhak's prayer for children was accepted only because he was the child of Avraham, so that it was Avraham who enabled Yitzhak to be a father.
The verse "the father of the righteous will greatly rejoice," quoted by the Midrash, was referring to one who, since he merited a righteous child, must at least have been wise - so that he was capable of raising a child like this, a child who, already from birth, was prepared for holiness. Such a father will rejoice twice - first for his own child, and second for the grandchild that will be born in the future because his child's prayer for children will be accepted as the prayer of a righteous person who is himself the child of righteous person (tzadiq ben tzadiq). But one whose offspring is a wise child is himself neither righteous nor wise, because his child, like Rivkah, became wise through his own effort. For such an offspring, the father can rejoice only for the child, but not for the grandchild, because there is no assurance that his child, not being the child of a tzadik, will merit to have children of his own.
va-yomer ha-qol qol ya'akov v'ha-yadayim y'dei eisav . . . va-y'var'kheihu (And he said: "The voice is Jacob's voice, but the hands are the hands of Esau" . . . so he blessed him.) (Genesis 27:21-22)
And it appears to our master that Rashi was compelled to comment that the words "the voice is Jacob's voice" mean that he speaks in an entreating strain - "Arise, I beg you" (qum nah) - because Ya'akov's voice and Eisav's voice sounded alike. For if not, Ya'akov would have feared that Yitzhak would surely recognize the sound of his voice. Now we know that Ya'akov fulfilled to the utmost degree the commandment to revere his father and always spoke to Yitzhak in an entreating manner. But he did not adequately fulfill the commandment to honor his father, for we know that he was punished for not doing so. Eisav acted in the opposite fashion, for he breached the law and spoke to Yitzhak in a harsh tone, without appropriate reverence - "let my father arise" (yaqum avi). However, Eisav, fulfilling the commandment of honoring his father to his utmost, constantly brought Yitzhak venison. And the Sages understood the verse "The boar from the forest ravages it" (y'khars'mena hazir mi-ya'ar) (Psalms 80:14) to be referring to Eisav, because, in his outward display of a piety, he was similar to a swine (which shows off its cloven hooves, seeking to appear as one of the ritually pure animals). Thus, Eisav used to treat his father generously, even as the Scripture says (Deuteronomy 15:8): "but you shall surely open your hand to him" (patoah tiftah et yad'kha lo), which is why his father loved him. So when Ya'akov brought savory meats to his father as his father loved, Yitzhak recognized that he was not only fulfilling the commandment of honor, but that he was also speaking in a soft and respectful way. Believing that Eisav had now fulfilled both commandments (honor and reverence), Yitzhak felt that Eisav now truly deserved to be blessed. So when Yitzhak said "the voice is Ya'akov's," he meant that he was being spoken to with the reverence of Ya'akov, and when he said "and the hands are the hands of Eisav," he meant that he was being treated with the generosity of Eisav. That is why Yitzhak blessed him.
va-yeherad yitzhaq haradah g'dolah ad m'od va-yomer mi eipho hu ha-tzad tzayid va-yavei li va-okhal mi-kol b'terem tavo va-avarakheihu gam barukh yih'yeh (Then Isaac trembled violently and said, "Who was it then that hunted game and brought it to me, and I ate it all before you came, and I have blessed him? - yes, and he shall be blessed.") (Genesis 27:33)
See Rashi and the Ramban who both resorted to forced explanations for Yitzhak's change from his initial fear and trembling and seething anger to then bless Ya'akov with a full heart and to reaffirm that Ya'akov would be blessed. The difficulty before us is that Yitzhak said "thy brother came with guile" (ba ahikha b'mirmah), and we know that the word "mirmah" always indicates a transgression. Nevertheless, Rashi felt obliged to interpret "mirmah" as "hokhmah" (cleverness).
And it appears to our master to say simply that this verse was summarizing the entire incident. First, "Yitzhak trembled violently" (va-yeherad yitzhaq haradah g'dolah ad m'od) and in the heat of his anger he asked "who then was it that hunted game?" (mi ei-pho hu ha-tzad tzayid). But in the end, his anger subsided and he confirmed the original blessing. The Scripture then recounts each point separately, explaining how every one came about. First the Scripture says (Genesis 27:34-35):
And when Esau heard the words of his father, he cried with a great and exceedingly bitter cry and he said, "Bless me, even me also, O my father!" And he said, " your brother came with cunning and has taken away your blessing." (ki-sh'moa eisav et divrei aviv va-yitzaq tz'aqah g'dolah u-marah ad m'od va-yomer bar'kheini gam ani avi. va-yomer ba akhikha b'mirmah va-yiqah et birkhatekha.)
These words of Yitzhak were spoken in anger. By saying that "your brother came with cunning" (ba ahikha b'mirmah), he meant that Ya'akov had committed an iniquity which is prohibited, not that Ya'akov had been clever (ormah) which would have been permissible. In saying this, Yitzhak intended to reassure Eisav that Ya'akov's actions would not avail him at all, because Ya'akov, having acted deceptively, would not achieve his goal. However, hearing this reassurance, Eisav responded (Id. 36), "Is he not rightly called Jacob? For he has supplanted me these two times. He took my birthright; and behold now he has taken away my blessing." (ha-khi kara sh'mo ya'aqov va-ya'aqveini zeh pa'amayim et b'khorati laqah v'hineih atah birkhati) With these last words, Eisav poured salt on his own wounds, because the anger of Yitzhak was thereby abated. For now Yitzhak understood that Ya'akov was truly the first-born, so that he took the blessings by right. In that case, the Scripture continues (Id. 37), "what then can I do for you, my son? Behold I have made him your lord, and all his brothers have I given to him for servants." So the verses 34-37 come to explain and elaborate on the earlier passage in verse 33 from "And Isaac trembled violently (va-yeherad yitzhaq haradha g'dolah ad m'od) until "yes, and he shall be blessed" (gam barukh yih'yeh).
And one of our master's students brought a clear proof to this from the text in verse 34 which, instead of saying "and it was when Eisav heard" (va-y'hi ki-sh'moa Eisav) says "when Eisav heard" (ki-sh'moa Eisav), which implies that the Scripture is recapitulating to explain what was said previously, not providing a narrative of further events. And this is very correct.