The commandments of the Torah are divided into the three general categories of Eidos, Chukim and Mishpatim -- testimonies, decrees and laws. The difference between them regarding their degree of comprehensibility is the following:
Mishpatim are those commands that are also dictated by mortal understanding, such as the obligation to honor one's parents and the prohibition against stealing.
Eidos are commandments that recall and/or testify to past significant historical and Jewish events, such as Shabbos and Pesach. Although not necessarily dictated by reason, once the commandments were given they are understood logically as well.
Chukim are those commands that have no rational explanation; moreover, they defy reason. These commandments are performed not out of any sense of understanding, but because a Jew accepts upon himself the "Yoke of Heaven," Kabbolas Ol Malchus Shomayim.
In other words, Mishpatim and Eidus commandments are Divine Will contracted and vested within the framework of logic, so that mortal man may be able -- to some extent -- to grasp and comprehend them.
Chukim, however, are entirely different. Here the Divine Will has not clothed itself in the garments of rationality, and is therefore found below in the same manner that it is found above -- essential Divine Will that entirely transcends intellect.
Since Chukim are the essence of Divine Will that is bound up with G-d's Essence -- for which reason it did not descend into the realm of intellect in the first place -- it is therefore necessary for man to perform them with the essence of one's soul, i.e., with the sense of Kabbolas Ol and total self-effacement that derives from the essence of one's soul and that far surpasses a person's revealed soul powers.
The mainstay of all Chukim is the Chok of Parah Adumah, the purification ritual of the Red Heifer. Thus the Midrash relates that even King Solomon, the wisest of men, who could understand the most abstruse and recondite matters of intellect, up to and including the reasons for all other Chukim, despaired at understanding the commandment of Parah Adumah.
His reason for despair stemmed from the fact that Parah Adumah seems to be utterly inexplicable, as it combines two opposite elements: it brings purity to the impure and rendered the pure impure. Concerning this decree, King Solomon admitted: "I said, 'I will gain wisdom,' but it is distant from me."
In fact, only Moshe merited to have Parah Adumah explained to him. And this explanation, too, was not a logical one, for as mentioned above Parah Adumah wholly transcends logic. Rather, the sanctity and self-abnegation of Moshe was such that he was able to palpably feel the Divine Will emanating within the commandment of Parah Adumah.
This is also one of the reasons why Parah Adumah is considered the general aspect of the Torah. Which is why the verse employs the terminology "This is the chukah of the Torah," rather than "This is the chukah of the Red Heifer." By doing so the Torah indicates that Parah Adumah is a foundation for the entire Torah and its commandments, Mishpatim and Eidos included.
The reason for this is because all Torah commands, even Eidos and Mishpatim, are fundamentally expressions of the Divine Will that utterly transcends logic. Merely, with regard to Eidos and Mishpatim it was G-d's desire that the Divine Will underlying these commands also descend within the realm of reason.
Since the aspect of Transcendent Will finds its greatest expression in the commandment of Parah Adumah, it is therefore deemed to be the general and overall aspect of Torah. As such, its proper performance necessitates the service of the soul's essence. This is accomplished through one's connection to Moshe, to whom the "reason" for Parah Adumah was revealed.
This is why with regard to Parah Adumah the verse states "They shall take unto you [Moshe] a Parah Adumah." It was Elazar, Aharon's son, who actually occupied himself with the preparation of the Parah Adumah. Why, then, was it necessary for the Parah Adumah to be taken "to you"?
But it was specifically Moshe who enabled the Jewish people throughout the generations to tackle something so difficult as the Parah Adumah. This also explains why all subsequent Parah Adumahs, including the tenth that will be used in the time of Mashiach, will utilize some of the ashes that were of the first Parah Adumah that Moshe prepared in the desert.
It is Moshe -- and the Moshe of each subsequent generation -- that is able to touch the very core of each and every Jewish soul, enabling them to properly perform the commandments with the quintessential essence of their being.
Based on Likkutei Sichos, Vol. IV, pp. 1056-1057.
We read in the section of Chukas that as a result of the various complaints of the Jewish people, they were attacked in the desert by venomous snakes. The people approached Moshe and said, "We have sinned by speaking against G-d and you; pray to G-d and have Him take the snakes away from us."
G-d told Moshe to construct and fabricate the image of a venomous snake and place it on a high pole, and "everyone who is bitten shall look at it and live." Thereupon, "Moshe made a copper snake and placed it on a high pole; whenever a snake bit a man, he would gaze at the copper snake and live."
Rashi, quoting our Sages, comments: "Does a snake cause death or life? Rather, when the Jewish people turned their eyes heavenwards and subjugated their hearts to their Father in Heaven, they were healed...."
Rashi also notes that though G-d did not specifically instruct Moshe to make the snake of copper, Moshe chose to make it of this metal since in Hebrew snake is nachash and copper is nechoshes, so that nechoshes contains within it the word nachash.
Since Moshe's fashioning the snake of copper is specifically mentioned in the Torah, we apprehend that this detail as well is related to the general aspect of the healing that came as a result of the "snake." What was so special about the snake being made of copper?
This will be understood by first comprehending how the healing of the Jewish people came about through the "snake."
From the above quoted verses it is obvious that the snakebites were so venomous that those bitten surely would have died were it not for "whenever a snake bit a man, he would gaze at the copper snake and live." [Additionally, the "snake" itself connotes death, as death was decreed as a result of the sin of the Tree of Knowledge, brought on through the instigation of the snake.]
Since the bites were so deadly that only by gazing at the copper snake was new life infused into the snakebitten individual, those "who gazed and lived" underwent something akin to the Revival of the Dead (Techiyas HaMeisim).
The power to "revive the dead cannot possibly emanate from 'the source of life,' " since "once the life force has already departed, it is impossible for it to be drawn down again from this very same level, to revive the one who has died."
Rather, "it derives from G-d's infinite abundant mercy that is even higher than 'the source of life.'" This level of spirituality can revive even those who have passed on since "there life and death are entirely equal, for which reason even one who is dead may live."
This explains how those who were bitten were healed by "gazing at the copper snake," for since there was drawn down this infinitely lofty level where "life and death are entirely equal" a total and absolute change was brought about, so that even the snake whose property is death was so transformed that it served as a source of life.
In order to draw down the divine effulgence that transforms the "snake" -- the attribute of death -- into the quality and infusion of "life," Jews must first serve and return to G-d through a form of spiritual service that is similar to the infinite abundant mercy that is being drawn down. This is the aspect and service of "subjugating their hearts to their Father in Heaven."
For "subjugation" implies that the entire heart -- not only the inclination for good, but the inclination for evil as well, the "snake" in man -- is transformed. Thus, instead of it opposing G-dliness and holiness, the evil inclination is so radically changed that it too is bound up with and subjugated to G-dliness.
The relationship between nechoshes (copper) and nachash (snake), and the reason why Moshe specifically made the nachash of nechoshes will be understood accordingly.
Chassidus explains that similar to nachash, nechoshes as well denotes a grade and rung that descends into unholiness. Indeed, since the Hebrew name for an object or living being denotes its source of life, this is why nechoshes derives from the word nachash, as the two are so closely related.
When man through his spiritual service transforms the "snakes" of the world into spirituality and holiness, the aspect of nechoshes is automatically transformed as well.
Based on Likkutei Sichos, Vol. XIII, pp. 71-76
1. See discourse titled Lech Lecha 5666.
2. Bamidbar Rabbah 19:3; Tanchuma, Chukas 6.
3. Koheles 7:23.
4. See Likkutei Torah beginning of Chukas, 56a.
5. Bamidbar 19:2.
6. See Sefer HaMaamarim Kuntreisim, Vol. II, p. 312a; see also Iggeres HaKodesh, Epistle XIX (p. 129a).
7. Bamidbar, ibid.
8. Bamidbar 21:4-10.
9. Ibid., verse 8.
10. Ibid., verse 9.
11. Discourse titled Ner Chanukah 5670; discourse titled Yichayeinu m'Yomayim 5701, ch. 1.
12. Yichayeinu m'Yomayim, ibid.
13. Ner Chanukah, ibid.
14. See Zohar, Vol. I, p. 35b, "And the snake -- This refers to the evil inclination."
15. Biurei HaZohar (Tzemach Tzedek) Pekudei, p. 320. See also Likkutei Sichos, Vol. VI, p. 158ff.
16. Or Torah (Horav HaMaggid) end of Bereishis (4b); Shaar HaYichud VehaEmunah ch. 1.