The Reasons for Commandments

  • Harav Aharon Lichtenstein

Sicha for Shabbat from the Roshei Yeshiva
Yeshivat Har Etzion



The Reasons for Commandments

Summarized by Ze'ev Frimer


Therefore the children of Israel shall not eat the sinew of the vein (gid ha-nasheh) that is upon the hollow of the thigh, to this day, because he touched the hollow of Ya'akov's thigh in the sinew of the vein. (Bereishit 32:33)

The Gemara (Chullin 101b), and subsequently the codifiers of the mitzvot, regard this verse not as a description of custom but rather as a real prohibition. But the Rambam, in his Commentary on the Mishna (end of chapter 7 of Chullin), teaches an important and fundamental principle:

Pay attention to the great principle included in this mishna, namely: ... whatever we refrain from doing or whatever we perform today we do only by the command of the Holy One through Moshe Rabbeinu, and not because the Holy One told it to the prophets before him. For example, the fact that we do not eat a limb from a living animal is not because the Holy One prohibited it to Noach, but rather because Moshe forbade us from eating the limb of a living animal because it was commanded to him at Sinai as a prohibition. Likewise, we do not perform circumcision because Avraham circumcised himself and the members of his household, but rather because the Holy One commanded us through Moshe Rabbeinu that we should circumcise as Avraham our forefather did. Likewise the sinew of the vein - we follow not the prohibition to Ya'akov but rather the command of Moshe. Did [the Rabbis] not teach, "613 commandments were told to Moshe at Sinai" - and all of the above are included in that number.

It would seem that we may question what difference it makes in principle whether we perform a mitzva because God commanded it to Avraham or whether we perform it as a result of God's revelation at Mount Sinai. Is the ultimate result not the same - i.e., that we perform the mitzva because it is the will of God, and we thereby fulfill His will?

The answer to this question relates to three aspects:

A) From the point of view of the person accepting the mitzva:

Had we fulfilled the mitzva as a function of God's command to Avraham, the performance of the mitzva would have resulted from a command given to an individual. However, in performing a mitzva due to God's command to the nation of Israel through Moshe, we fulfill the command as part of Knesset Yisrael in its entirety, which accepted the command upon itself directly. The performance of a mitzva that was given to an individual, a "third person," is not the same as the performance of a mitzva given to all of the nation of Israel, which includes each one of us.

B) From the point of view of the nature of the mitzvot:

When we perform a mitzva as a result of God's command to the forefathers, all the mitzvot assume the nature of a motley collection of instructions and rules, for some commands were given to one person, and some to another. The mitzvot are thereby reduced to an ad-hoc list of orders. This is not the case when we perform a mitzva because we received the Torah in its entirety as a single, organic, complete unit given to Am Yisrael through Moshe. In this instance, the mitzvot are perceived as "torat Hashem temima" - the whole, complete, perfect word of God - and the performance of an individual mitzva is perceived as a part of that complete entity.

C) From the point of view of the significance attached to the performance of the mitzva:

When we perform a mitzva that is part of that Divine law given by God at Sinai, then the mitzva entails recollection of that elevated occasion, that one-time experience when God was revealed to our nation face to face, when we heard the "voice of the living God speaking from within the fire." The meaning of that event and its power come to mind, expressed in the performance of a command given to Moshe at Sinai. These are completely absent when performing a mitzva as the result of God's command to one of the forefathers, and therefore the fulfillment is lacking.

Nevertheless, a command to the forefathers and the circumstance surrounding it are still of great significance. The historical origins of the mitzva have significance for the long term, since "The deeds of the forefathers serve as a sign for the children." The midrash on the verse concerning the gid ha-nasheh portrays one aspect of this historical significance:

"And [the angel] touched the hollow of [Ya'akov's] thigh" - He touched [i.e. injured] the righteous men and women, the male and female prophets, who were destined to learn from him. And who are these? This refers to a generation subject to anti-Jewish decrees." (Bereishit Rabba 77:3)

(This sicha was delivered on Shabbat parashat Vayishlach 5759 [1998].)


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