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מכרה כיום, “sell me as of this day!” Rashi understands the word כיום as describing the transaction about to take place to be as clear and beyond misunderstanding as daylight, which illuminates everything clearly. The plain meaning of the word is: “immediately,” as, for instance in Samuel I 2,16 קטר יקטירון כיום את החלה, “let me first burn the fat presently, etc.” Onkelos, taking into account that the sale under discussion will become effective only after Yitzchok’s death, understands the word כיום to mean “as and when, with retroactive closing date as of today.” Some commentators understand Yaakov as saying that the sale, trade, will be effective only today when you are close to death. It is appropriate that you receive some of this dish now for once you have died the entire inheritance of our father will automatically come to me. Esau admitted that Yaakov was right and proceeded to gulp down the red dish. The major problem with the whole transaction is that a birthright has never been understood as something that can be acquired or disposed of by selling and buying. What kind of procedure represents the transfer of the object being sold to the buyer, i.e. what מעשה קנין is there possible? If the object of the sale was the double share of the father’s inheritance decreed by the Torah for the firstborn, we have learned that if someone says “I sell you what I will inherit from my father,” that such a declaration is legally quite meaningless. (Baba Metzia 16) Some resolve this problem by saying that seeing Yaakov should by rights have been the firstborn as he was formed out of Yitzchok’s first drop of semen, and that Esau was born first only because he pushed himself ahead at the time of the delivery, he did not even need to make a קנין, act of acquisition, for something which rightfully was his in the first place. We do not think that this argument is tenable, as the Torah specifically calls the “first born” the one that emerges first from the mother’s womb. (Exodus 13,2) Others hold that Yaakov was convinced that his father was going to deed him all his belongings during his lifetime, just as Avraham had deeded all his belongings to Yitzchok during his lifetime. He would do so in order to forestall any legal protest by Esau when the time came. Still other Rabbis claim that the word בכורתך did not refer to inherited wealth at all, but to the dignity, the standing among his peers that the senior brother usually commands. Yaakov wanted to trade the dish of lentils he was about to give to Esau for that intangible symbol of dignity. Still other sages say that all Yaakov was about to buy from Esau was anything that he might inherit from his father on this very day, (if his father were to die on that day). If so, such a sale would be legally valid. Yaakov used the words מכרה כיום to clarify that legal point. When hearing this, Esau said: ”what good is the birthright to me that you want to buy from me only what might accrue to me this day, seeing that I am not going to outlive my father anyway, you might as will buy my future share in any birthright also.” This is why the Torah testifies in a line later on that Esau displayed his disdain for the birthright. (verse 34) In any event, seeing that the part of the transaction described by Yaakov with the words מכרה כיום was legally valid, any codicil, such as proposed by Esau, would be valid also. Esau seized upon that point later on when he accused Yaakov of ויעקבני זה פעמים (27,36) referring to the fact that Yaakov had tricked him into this codicil, something that would not have had legal standing but for his having first agreed to the sale of limited duration, i.e. מכרה כיום. My late father, the רא'ש of blessed memory, seized on this detail to rule that when someone sells something to one’s neighbour which is not subject to regular methods of acquisition, such as “what I am going to inherit from my father,” or “a loan which I have outstanding for repayment with X and secured only by an oral promise to repay,” both objects not subject to sale in the accepted sense of the word, and the seller adds an oath to his verbal sale, such a sale has become valid, and the court can enforce the terms of the sale from the seller due to the seller having obligated himself by oath. This is all derived from the pains Yaakov took to legalise the sale for the day on which it was concluded by adding the words “swear it to me,“ to Esau.
ויבז עשו את הבכורה, “Esau had already displayed disdain for the asset known as birthright.” This is why Yaakov bought it from him. We find that Rabbi Yehudah Hachassid, referring to this verse, claims that if one finds a confirmed sinner in the possession of holy texts such as a Torah scroll, it is permissible to use subterfuge to get him to sell it.
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when he wills his property to his sons, he may not treat as first-born the son of the loved one in disregard of the son of the unloved one who is older.
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