The boys grew up [and their differences became recognizable]. Eisav was a man who knew how to trap [people with his mouth], a man of the field [who enjoyed hunting]. Ya'akov was an honest person, dwelling in tents [the Yeshivah of Sheim and Aiver].

-- Breshis 25:27

Classic Questions

How did Eisav trap? (v. 27)

Rashi: He knew how to trap and deceive his father with his mouth, asking him, "Father, how do we separate ma'aser [tithes] from salt and straw?" This made his father think that he was precise in the observance of mitzvos.

Mizrachi: Why did Rashi not interpret the term "trap" literally, to mean trapping animals? Rashi was troubled by the repetition of the verse, "Eisav was a man who knew how to trap, a man of the field." Surely, these two expressions both mean the same thing, so why did the Torah make an unnecessary repetition? Rashi understood that "knew how to trap" must be referring to something else besides hunting, i.e., his ability to trap others with his mouth.

Eisav's question, "How do we separate ma'aser [tithes] from salt and straw?" was deceptive because there is in fact no obligation in Jewish Law to separate ma'aser from salt or straw (ma'aser is only separated from agricultural produce). This would have led Yitzchak to think that Eisav was extremely particular in mitzvos, going beyond the letter of the law to separate ma'aser even in a case where there is no obligation to do so.

Maskil leDavid: Surely, by asking "How do we separate ma'aser [tithes] from salt and straw?" Eisav would have appeared to be an ignoramus, who did not know the basic law that ma'aser is only taken from agricultural produce? We must assume that Eisav was actually asking, "Since I am separating this as an additional stringency, not as a legal requirement, perhaps I should make some indication of this fact by altering some of the procedures?"

Bartenura: Eisav was not asking how to take ma'aser, since the answer to this is obvious: one simply separates a tenth of the produce.

The Rebbe's Teachings

Rashi's Problem (v. 27)

In addition to the answers of the commentators, the following could be argued: Rashi was troubled by why the verse states, "Eisav was a man who knew how to trap, a man of the field." Surely, the appropriate sequence should be "a man of the field who knew how to trap," for one only starts trapping after going out into the field. Due to this problem, Rashi concluded that the "trapping" must have occurred at home, before Eisav went out "to the field."

What "trapping" could be done in the house? Answers Rashi: "He knew how to trap and deceive his father with his mouth."

Eisav's Deceptive Question

Rashi's comment, that Eisav asked his father, "How do we separate ma'aser [tithes] from salt and straw?" is somewhat perplexing. Since salt and straw are in fact exempt from ma'aser, Eisav's question would seem to display ignorance rather than precision in the observance of the mitzvos (as Maskil leDavid writes).

Maskil leDavid (and Mizrachi) answer that Eisav indicated to his father that he wished to separate ma'aser beyond the letter of the law, even from his possessions that were exempt from ma'aser.

However, from Rashi's choice of words this does not appear to be the case. Eisav said, "How do we separate ma'aser from salt and straw?" Taking this statement at face value, it appears that Eisav did think that salt and straw were obligated in ma'aser. So what, then, was Eisav's trap?

The Explanation

Earlier, in Parshas Lech Lecha, we read, "[Avram] gave him a tenth ["ma'aser"] from everything" (14:20). Rashi writes, "Avram gave him ma'aser from all his possessions, because Malkitzedek was a priest."

Here we see that at the literal level of Torah interpretation, Avraham did indeed give ma'aser from all his possessions ("everything") and not only from agricultural produce. Presumably, the clause that ma'aser is only separated from agricultural produce must have been added later, with the giving of the Torah (see Toras Menachem on Lech Lecha ibid.).

Since Avraham commanded "his household after him to keep the way of G‑d, doing charity and justice" (ibid 18:19), we can assume that Yitzchak too was educated to separate ma'aser from all of his possessions (in addition to the Torah's explicit statement that he separated ma'aser from agricultural produce—26:12, and Rashi ibid.). Likewise, Yitzchak would have taught Ya'akov and Eisav to give ma'aser from all their personal belongings too.

In this light, Eisav's question, "How does one take ma'aser from salt and straw?" was quite appropriate, as in their household it was customary to take ma'aser from all possessions, even salt and straw.

We are now only left with one question: What exactly was Eisav asking with his inquiry? Surely, one separates ma'aser from salt and straw by simply taking off a tenth (as Bartenura says)?

However, there is a complication with salt and straw, as they are both substances of very little value, but when they are mixed with other things they can prove extremely important. E.g., salt is not merely a seasoning for food, but it brings out the flavor of the entire dish, without which it is tasteless. Similarly, straw as it stands alone is mere animal fodder, but mixed with other components it can make bricks (see Shemos 5:7).

Hence, in an attempt to appear pious in his father's eyes, Eisav devised an ingenious question: Do we simply take a tenth of the salt or straw as it is worth now, or do we take into consideration their increase in value when used in a final product, since that is when their genuine use becomes apparent? This would make a practical difference when the ma'aser was separated, because Avraham's custom (which he passed on to his children) was not to separate ma'aser from each type of produce individually, but rather to take a tenth of the value of "all his possessions" collectively. Thus, there would be a difference in the total amount of ma'aser, depending on whether the salt and straw were evaluated as raw materials or not.

"This made his father think that he was precise in the observance of mitzvos," as Eisav appeared to be paying attention to subtle details within the obligations incumbent upon him.

(Based on Likutei Sichos vol. 25, p. 116ff)