Commentary for Horayot 1:3
הוֹרוּ בֵית דִּין לַעֲקֹר אֶת כָּל הַגּוּף, אָמְרוּ, אֵין נִדָּה בַתּוֹרָה, אֵין שַׁבָּת בַּתּוֹרָה, אֵין עֲבוֹדָה זָרָה בַתּוֹרָה, הֲרֵי אֵלּוּ פְטוּרִין. הוֹרוּ לְבַטֵּל מִקְצָת וּלְקַיֵּם מִקְצָת, הֲרֵי אֵלּוּ חַיָּבִין. כֵּיצַד. אָמְרוּ, יֵשׁ נִדָּה בַתּוֹרָה, אֲבָל הַבָּא עַל שׁוֹמֶרֶת יוֹם כְּנֶגֶד יוֹם פָּטוּר. יֵשׁ שַׁבָּת בַּתּוֹרָה, אֲבָל הַמּוֹצִיא מֵרְשׁוּת הַיָּחִיד לִרְשׁוּת הָרַבִּים, פָּטוּר. יֵשׁ עֲבוֹדָה זָרָה בַתּוֹרָה, אֲבָל הַמִּשְׁתַּחֲוֶה פָטוּר, הֲרֵי אֵלּוּ חַיָּבִין, שֶׁנֶּאֱמַר (ויקרא ד) וְנֶעְלַם דָּבָר, דָּבָר וְלֹא כָל הַגּוּף:
If beth-din ruled to uproot the entire body [i.e., all of the principles of the mitzvah] — if they said: There is no (institution of) niddah in the Torah, there is no Shabbath in the Torah, there is no idolatry in the Torah, they are exempt (from an offering), [it being written (Leviticus 4:13): "And there be hidden a thing" — Read it: "And there be hidden from a thing," part of the thing and not the whole thing.] If they ruled to nullify part and to fulfill part, they are liable (for an offering). How so? If they said: There is niddah in the Torah, but one who lives with a woman "who guards a day (of taharah [cleanliness] against a day of tumah [uncleanliness]" is not liable (to kareth). [(The Gemara asks: But guarding a day against a day is written in the Torah, viz. (Leviticus 15:22): "Then she shall count for herself," whence we learn that she counts one (day of taharah) against one (day of tumah), and for anything written in the Torah beth-din do not bring an offering! And the Gemara answers: We are speaking of an instance in which they said that zavah (a woman with a flow) obtains only in the daytime; that is, only when she sees blood in the daytime and not when she sees it at night, it being written (Ibid.) "all the days of her flow")]; (if they said:) there is Shabbath in the Torah, but one who carries from a private domain to a public domain is not liable [i.e., if they said: Bringing in and taking out is forbidden, it being written (Exodus 16:29): "Let no man go out of his place," but throwing and reaching out is permitted.)]; there is idolatry in the Torah, but bowing down is not liable, [i.e., if they said that bowing down where there is prostration of hands and feet is forbidden, it being written (Exodus 34:14): "You shall not bow down to another god," but where there is no prostration it is permitted], they are liable (for an offering), it being written (Leviticus 4:13): "And there be hidden a thing" — a thing and not the whole body (of the mitzvah). [In sum: Beth-din is not liable until they rule (permitted) on a thing that the Sadducees do not concede (as being forbidden; but if they ruled (wrongly) on a thing that the Sadducees concede (as being forbidden), they are exempt from a congregational offering. And, as to the many who transgressed by their ruling, each one is liable to bring an offering for his unwittingness. Why so? For this is an instance of "Go and read it in the house of the master," (i.e., you should have known it.)]
Bartenura on Mishnah Horayot
English Explanation of Mishnah Horayot
If, however, they ruled that a part [of a commandment] was to be annulled and a part fulfilled, they are liable. How is this so? If they said: [the law concerning the] menstruant occurs in the Torah but if a man has relations with a woman that awaits a day corresponding to a day he is exempt, [or that the law concerning the] Sabbath occurs in the Torah but if a man carries anything from a private domain to a public domain he is exempt, [or that the law of] idolatry occurs in the Torah, but if a man only bows down to an idol he is exempt, they are liable, for it says, “And if some matter escapes [the notice of the congregation]” (Leviticus 4:13), “some matter” but not the entire principle.
Our mishnah teaches that if the court rules that an entire commandment does not exist, they are not liable. Whereas if they rule that one part of the commandment does not exist, they are liable.
This mishnah teaches an important principle for establishing when the court is liable to bring the special sin-offering for having made a wrongful ruling. If the court were to state that the entirety of a well-known commandment does not exist, and people were to act upon the court’s ruling, the people who actually sin are liable and not the court. Since these three things, the prohibition of sexual relations with a menstruant, the prohibition of Sabbath laws and the prohibition of idol worship are so clearly stated in the Torah, everyone should have known that the court erred when it ruled that these things don’t exist. This is not even truly considered a ruling by the court, but merely an empty statement against the Torah. While interpretation of the Torah is flexible, it does have its limits.
However, if the court rules that a certain act which is one part of a larger prohibition, is permitted, and people act upon the court’s ruling, the court is liable and not the people. For instance, a woman who sees blood at a time when she is not supposed to be menstruating must wait one day for every day that she saw blood before she can resume sexual relations. If the court ruled that one could have relations with such a woman, they are permitting an act which is against the Torah. Similarly, if they permit a person to remove an object from one domain to another on Shabbat, they are permitting carrying, which is forbidden. Finally, if they admit that idol worship is prohibited, but bowing down is not considered idol worship, they have made an errant ruling. In all of these cases, since they admit that the commandment exists, but have made an error on a detail (these are all well-known and rather large details in rabbinic literature), they are liable if the people listen to their ruling. People might not have known that such actions were prohibited, even though they knew that the general commandment exists. Therefore, they are not liable for following the court’s ruling.
The mishnah ends with a midrash supporting this view. One can understand the word davar to mean “part of the matter”; from here the rabbis learn that if the whole matter escapes the court, the court is not liable.
Questions
Why do you think the rabbis posited this exception to the general rule of the court’s culpability for errors?