"And the man who shall do": (A rebellious elder is not liable) until he teaches to do (what is contrary to the ruling of the Sanhedrin, [but not if he only voices disagreement with their ruling]).
"to the Cohein who stands to serve": (Ibid. 18:5) "to stand to serve" tells me that the service (of the Cohein) is only "standing." This tells me only that it is a mitzvah (for him to stand). Whence do I derive that it is a categorical requirement (i.e., that it is not valid unless he is standing)? "who stands to serve" implies that if he sits, his service is invalid.
(דברים יז יב) וְהָאִישׁ אֲשֶׁר יַעֲשֶׂה בְזָדוֹן, אֲשֶׁר לֹא שָׁמַע מִפִּי בֵּית דִּין וּמוֹרֶה.
(Devarim 17:12) "And the man who shall do wilfully, not to listen": to its ruling.
אֲשֶׁר יַעֲשֶׂה – עַל מַעֲשֶׂה הוּא חַיָּב וְאֵינוֹ חַיָּב עַל הוֹרָיָה.
"And the man who shall do": (A rebellious elder is not liable) until he teaches to do (what is contrary to the ruling of the Sanhedrin, [but not if he only voices disagreement with their ruling]).
בְזָדוֹן – עַל זָדוֹן הוּא חַיָּב וְאֵינוֹ חַיָּב עַל שְׁגָגָה.
"wilfully": He (the rebellious elder) is liable only for witting and not for unwitting transgression.
לְבִלְתִּי שְׁמֹעַ – וְלֹא שׁוֹמֵעַ מִפִּי שׁוֹמֵעַ.
"not to listen to the Cohein": (directly), but not ("not to listen") to one who hears it from him.
אֶל הַכֹּהֵן הָעֹמֵד לְשָׁרֵת, מַגִּיד שֶׁאֵין שֵׁרוּת כָּשֵׁר אֶלָּא מֵעוֹמֵד. הָא אִם יָשַׁב וְעָבַד – עֲבוֹדָתוֹ פְּסוּלָה.
"to the Cohein who stands to serve": (Ibid. 18:5) "to stand to serve" tells me that the service (of the Cohein) is only "standing." This tells me only that it is a mitzvah (for him to stand). Whence do I derive that it is a categorical requirement (i.e., that it is not valid unless he is standing)? "who stands to serve" implies that if he sits, his service is invalid.
אוֹ אֶל הַשּׁוֹפֵט – זֶהוּ שֶׁאָמַרְנוּ: אַף עַל פִּי שֶׁאֵין בּוֹ כֹּהֲנִים וּלְוִיִּם כָּשֵׁר.
"or to the judge": This is as we said: Even if there are no Cohanim and Levites there, it is valid.
וּמֵת הָאִישׁ – בִּסְתָם מִיתָה הָאֲמוּרָה בַּתּוֹרָה, בְּחֶנֶק.
"that man shall die": the unqualified death penalty in Scripture — strangulation.
הַהוּא – לֹא אָנוּס וְלֹא שׁוֹגֵג וְלֹא מֻטְעֶה.
"that man": and not one who is forced or unwitting or under some misapprehension.
וּבִעַרְתָּ הָרָע מִיִּשְׂרָאֵל – בַּעֵר עוֹשֵׂי הָרָעוֹת מִיִּשְׂרָאֵל!
"and you shall remove the evil from Israel": Remove the doer of evil from Israel.