Musar for Yevamot 39:20

The general principle of Separation is what our sages of blessed memory said: "sanctify yourself [by abstaining] of what is permitted to you" (Yevamot 20a). This is the meaning of the word "Separation" itself. That is to say - to separate and distance from the thing, prohibiting on oneself something which is permitted. The intent in this is to not come to violate the prohibition itself.

The beginning of our portion deals with קדושת הגוף, attaining sanctity of one's body. Nachmanides (Chavel edition page 115) – as distinct from the Midrash Rabbah quoted by Rashi – does not see in this a directive to be separate, to refrain from incest, etc., but understands it to mean that people who qualify for the description קדושים, holy, are the ones who have sanctified themselves not by abstaining from what is forbidden, but by abstaining from what is permitted, each person according to his individual urges. Our sages (Yevamot 20a) have called this process קדש עצמך במותר לך, "sanctify yourself by denying yourself something you are entitled to!" From the above we learn that to a certain extent every single person has his own Torah. Assuming that every person had the same natural tendencies, and that every day or hour of the year would be identical to each other [that there would not be a predisposition to seek warmth in the winter and a cooling breeze in the summer, for instance. Ed.], the Torah, when legislating what may or may not be eaten would simply write that: "a certain quantity of certain foods may be consumed, everything else is prohibited." The Torah would express itself in similar terms concerning with whom and how frequently one is allowed to have sexual intercourse. The Torah would find a way to phrase prohibitions of permitted speech and thought in a similar way. As it is impossible to state these prohibitions in such a detailed manner, the Torah has to allow for the differences in the nature of different people. It therefore contents itself with a general directive: "Strive to become holy!" The meaning of the directive of the Talmud to sanctify oneself by means of denying oneself enjoyment of things which are permitted in principle, is that a person must be mature enough to know what is permissible in accordance with his particular station in life and his particular natural tendencies. When a person feels himself to have attained a particular spiritual level he considers certain matters as forbidden to him though they may formerly have been perfectly permissible, and though they may still be perfectly permissible for others not on his spiritual level.

Sanctification of the body, i.e. refining the body is a preliminary for attaining sanctity of the spirit, for coming close to G–d. This is achieved through separating oneself from physically pleasurable experiences even when these are permissible, as we know from the statement of our sages קדש עצמך במותר לך, "if you wish to sanctify yourself do it by refraining from that which is permissible" (Yevamot 20). There are different kinds of "holiness;" all of them refine the body, prevent it from being something gross, and enable the person who is so sanctified to achieve mastery of mind over matter. When carried to the maximum extent possible, the body becomes an insignificant part of the total personality. When the Torah (Deut. 7,7) describes the reason G–d liked the Jewish people as כי אתם המעט מכל העמים "For you are the smallest of all the nations," the word המעט refers to the relative insignificance of the body of the Jew when compared to his mind, his soul. This is also the reason Amos 7,2 describes Jacob as קטן, small. Compared to Esau the part the body plays in Jacob's total personality is insignificant, small. When Esau first emerged from his mother's womb, his body was full of the pollutants of the original serpent. By that time this pollutant had left the body of Rebeccah and Jacob emerged; he was predominantly spiritual and only marginally tainted with the remaining pollutant. The impurity of the menstruating woman is none other than the residual pollutant first absorbed by Eve when the serpent mated with her. Esau's being אדמוני, reddish looking, is a reflection of the quantity of the blood of menstruation. The liver is all blood. Pursuing one's physical desires, giving in to the "fire" of one's passions originates in the liver. "Fire" is synonymous with destruction. The reason such an unrefined person cannot come close to G–d is that the state of his body makes his contact with fire an experience that consumes him rather than one which "warms" him.