Halakhah su Levitico 18:8

(Aleph)⁶Starting from here, each paragraph begins with a letter from an acrostic that sequentially includes all of the letters of the Hebrew alphabet, followed by the author’s name. The Rabbis said (Bereishit Rabbah 8:5), “At the time that the Holy One, blessed be He, wanted to create man, He created a group of angels, etc. And they said (Ps. 8:5), ‘What is man that you should consider him’ [and so, they opposed his creation].” At first glance, [we would wonder] why the angels would care about man’s creation. [To answer this, we must understand the nature of man:] As the essence of man’s creation is [that he be] upon the earth. Even though the [human] soul benefits from the radiance of the glory from [the One from] which it has been hewn, and there is nothing lacking in the house of the King; [nevertheless] the Divine Wisdom, may His name be blessed, decreed that [the human soul] should be brought down [to the world], in order to test it with the performance of His commandments and the keeping of His Torah. And when ‘it is very righteous,’ ‘so will it multiply and so will it expand’ and ‘grow upwards,’ until ‘it returns to God who gave it’ ‘with great strength’ and ‘with abundance of power.’ And it is written in the Zohar 1:60a [to explain the verse in Prov. 5:15], “Drink water from your own cistern, running water from your own well”; [that] when the soul is above, it only has the aspect of a cistern, which does not [produce its own water], but is rather filled from others. In of itself, however, it is empty. But when it comes down to this lowly world and achieves what it is supposed to achieve – like the wisdom of His decree, may His name be blessed – then it has the aspect of a well, which is an overflowing spring and is emanating from itself. And in this way it will not [acquire] the bread of shame.⁷The roots of this this idea – that unearned reward is a source of shame – are from several places in the Zohar. See, for example Zohar 1:4a. The basis for the metaphor, however is found in Talmud Yerushalmi Orlah 1:3, 61b. And the first well-known use of the actual phrase is only found later in R. Yosef Karo’s Maggid Mesharim 2:8, which was written in the 1500’s. As the essence of the matter is that anyone who has nothing from himself is a poor person that is considered as if dead.⁸Zohar 2:119a, Nedarim 64b. This is as is written in Gur Aryeh,⁹Maharal, Gur Aryeh on Exod. 4:19:2. that the water of a well is called living waters because it [produces water] from itself (meaning, its underground spring) – which is not the case with the water of a cistern. And so this is why a poor person is considered as if dead. [Hence (as in Prov. 15:27)], “and the one who hates gifts, lives.” See there. And if so, the whole time that the soul is in its source, it has the aspect of a cistern that has no life; as it is empty from itself, besides from what is given to it. [This is] until it descends here and emanates from itself with the aspect of a well and has life. And this is why it states (Gen. 2:7), “He blew into his nostrils a living soul.” That is because the main aspect of the creation of man on the earth was so that the soul could have the aspect of “a living soul.” And this is [the meaning of], these are the commandments, “that a man should do and live through them” (Lev. 18:8).

Ramban, in his commentary on Yevamot 98a, joins many other scholars in questioning the propriety of Jacob's action in marrying two sisters, Rachel and Leah. Such marriages are explicitly enjoined by Leviticus 18:8 and rabbinic tradition maintains that the Patriarchs observed the commandments even prior to their revelation at Mount Sinai. This difficulty is resolved by other authorities in a variety of ways. Ramban offers an incisive explanation. Consanguineous relations are forbidden to Noachides, yet sexual liasons with close relatives of a spouse are incestuous only for Jews, but not for non-Jews. Ramban remarks that this is so because "ishut let lehu," i.e., non-Jews are excluded from the institution of ishut. Thus Jacob was able to marry his sister-in-law because, odd as it may sound, she was not the sister of a "wedded" wife. Assuredly, a relationship did exist between Jacob and his spouse, but it was significantly different from a sanctified matrimonial relationship since such relationships became hallowed only at Sinai.

To not reveal the nakedness of the wife of the father, even though she is not his mother: To not reveal the nakedness of the wife of the father, even though she is not his mother, as it is stated (Leviticus 18:8), "The nakedness of the wife of your father you shall not reveal."