Musar sur La Genèse 12:2

Know further that there are those with an evil temperament, Heaven spare us, whose eyes, mouths and hearts are rooted in the Sitra Achra. The curses of such individuals are extremely dangerous. Rabbi Yehudah HaChassid writes that malignant spirits called chitzonim are prepared to actualize these curses by lodging accusations against the victim. If the Holy One Blessed is He did not shield him on account of His promise to Avraham, “And you will be a blessing” (Bereishis 12:2), the curses would take effect on that person, Heaven forbid.

We therefore see that the patriarchs by their very lifestyles reveal the mystical aspects of Creation through their lifestyles as reported in the Torah. Bereshit Rabbah 1,10, commenting on why the Torah commences with the letter ב instead of the letter א, mentions several reasons. The Torah wishes to indicate that there are two worlds, the עולם הזה, and the עולם הבא. The letter ב symbolises ברכה, blessing. The letter א would have been inappropriate, because it is the first letter of the word ארור, cursed. Had the Torah started with א, many would have thought that this was proof that the whole enterprise of Creation was doomed to failure, i.e. cursed. As a result of such considerations, G–d decided to create the universe by using the letter ב first, hoping that the universe would endure. We see that both the Creation and (the lives of) the patriarchs express the concept of ברכה, blessing. It is fitting then that the source of, or better key to, blessings should have been placed in the hands of the patriarchs. G–d first told Abraham about this in Genesis 12,2 when He literally commanded him to become a source of blessing by telling him that he had become the repository of blessings. Isaac inherited this gift from his father as we see from Genesis 25,11 where G–d passed on Abraham's blessing to Isaac after Abraham's death. The competition between Esau and Jacob was about which of the two would be the heir to this power to bless with which G–d had invested Abraham and subsequently Isaac. Jacob became the heir to this power to bless, and he in turn bequeathed it to his children. Abraham did not personally bequeath these blessings to his son Isaac but waited for G–d Himself to do so. The reason for this will be explained when we deal with the blessing that Isaac bestowed on Jacob. We will also quote the comments of Bereshit Rabbah on that subject.

The Gentile slave obtains his release in the event any of 24 types of his limbs have been destroyed (Kidushin 24, Baba Kama 75). This is to remind us that man was created in the image of G–d (Genesis 1,27). Our sages explain that man's 248 limbs correspond to the number of the Torah's positive commandments. These in turn are symbolic of the 248 joints in the אדם העליון, man's spiritual counterpart in the Celestial Regions, who sits on the throne. This is why the first of the patriarchs, Abraham, was called אבר מה (the letters in his name being re-arranged). The מה, corresponds to the numerical value of the word אדם, which in turn is equivalent to the four lettered name of G–d spelled in letter form. =ה-א ,13=ו-א-ו ,6=ה-א ,20=י-ו-ד6, total=45. Abraham did not want to be associated through marriage with אליעזר, who is ארור, cursed, having been a descendant of כנען, who was cursed by Noach to remain a slave permanently (Genesis 9,25). It is not possible for ברוך and ארור, the blessed and the cursed, to be paired successfully. Abraham of course, was blessed, and so were his descendants (Genesis 12,2). Kabbalists perceive of ראשי אברים as referring to man at his moral best, i.e. אדם הפנימי, as well as a corresponding type of ראשי אברים, of the אדם החיצוני, man at his moral worst, i.e. man under the influence of Noach's curse. By destroying the ראש אבר of a Gentile slave, one releases that person from the influence of that curse. Therefore, he no longer needs to be a slave (as per Genesis 9,25). As a result, such a person can join the ranks of the free, the ones subject to G–d's blessing.