חולין ז׳Chullin 7

Mishnah 1א׳

גִּיד הַנָּשֶׁה נוֹהֵג בָּאָרֶץ וּבְחוּצָה לָאָרֶץ, בִּפְנֵי הַבַּיִת וְשֶׁלֹּא בִפְנֵי הַבַּיִת, בְּחֻלִּין וּבְמֻקְדָּשִׁים. וְנוֹהֵג בִּבְהֵמָה וּבְחַיָּה, בְּיָרֵךְ שֶׁל יָמִין וּבְיָרֵךְ שֶׁל שְׂמֹאל. וְאֵינוֹ נוֹהֵג בְּעוֹף, מִפְּנֵי שֶׁאֵין לוֹ כָף. וְנוֹהֵג בְּשָׁלִיל. רַבִּי יְהוּדָה אוֹמֵר, אֵינוֹ נוֹהֵג בְּשָׁלִיל. וְחֶלְבּוֹ מֻתָּר. וְאֵין הַטַּבָּחִין נֶאֱמָנִין עַל גִּיד הַנָּשֶׁה, דִּבְרֵי רַבִּי מֵאִיר. וַחֲכָמִים אוֹמְרִים, נֶאֱמָנִין עָלָיו וְעַל הַחֵלֶב:

[The prohibition against eating] the sciatic nerve applies in the land [of Israel] and outside of the land, during the time of the Temple and not during the time of the Temple, for chulin [animals or food permitted for general consumption] and for mukdashim [animals or food which are holy and not available for general consumption]. And it applies to domesticated and wild animals, for the right thigh and the left thigh. But it does not apply to a bird since it does not have a spoon [shaped hip]. And it applies to a fetus. Rabbi Yehuda says, "It does not apply for a fetus. And its chelev [fats around the stomach, intestines, and kidneys of some animals which are forbidden for eating] is permissible." "And the butchers are not believed regarding [the removal] of the sciatic nerve," in the words of Rabbi Meir. But the Sages say, "They are believed about it and about chelev."

Mishnah 2ב׳

שׁוֹלֵחַ אָדָם יָרֵךְ לְנָכְרִי שֶׁגִּיד הַנָּשֶׁה בְתוֹכָהּ, מִפְּנֵי שֶׁמְּקוֹמוֹ נִכָּר. הַנּוֹטֵל גִּיד הַנָּשֶׁה, צָרִיךְ שֶׁיִּטֹּל אֶת כֻּלּוֹ. רַבִּי יְהוּדָה אוֹמֵר, כְּדֵי לְקַיֵּם בּוֹ מִצְוַת נְטִילָה:

A person [may] send a thigh to a non-Jew with the sciatic nerve inside of it, since its location is recognized. One who removes the sciatic nerve needs to remove all of it. Rabbi Yehuda says, "In order to fulfill the commandment of removal."