וַיִּגְוַ֨ע יִצְחָ֤ק וַיָּ֙מָת֙ וַיֵּאָ֣סֶף אֶל־עַמָּ֔יו זָקֵ֖ן וּשְׂבַ֣ע יָמִ֑ים וַיִּקְבְּר֣וּ אֹת֔וֹ עֵשָׂ֥ו וְיַעֲקֹ֖ב בָּנָֽיו׃
And Yitzchak expired and died and was gathered to his people, old and full of days; and Eisav and Yaakov his sons buried him.
Bava Basra 16b (on the order of Esav and Yaakov at Yitzchak’s burial).
ויקברו אותו עשו ויעקב בניו — מִדְּאַקְדְּמֵיהּ אַדְבּוֹרֵי אַדְבְּרֵיהּ, וּמִדְּאַדְבְּרֵיהּ שְׁמַע מִינַּהּ תְּשׁוּבָה עֲבַד בְּיָמָיו.
“And Eisav and Yaakov his sons buried him” — since the Torah lists Eisav before Yaakov, it shows that Eisav let Yaakov take precedence; from this the Gemara infers that Eisav had repented during his lifetime.
Bava Basra 16b uses the order “Esav and Yaakov” as a parallel to the order of Yishmael and Yitzchak: when a younger son allows the elder to precede him, the Gemara infers acceptance of the elder’s authority and repentance.
Derash on the joint burial (Bereshit Rabbah).
Eisav and Yaakov together buried Yitzchak.