וַיַּ֨עַן יִצְחָ֜ק וַיֹּ֣אמֶר לְעֵשָׂ֗ו הֵ֣ן גְּבִ֞יר שַׂמְתִּ֥יו לָךְ֙ וְאֶת־כָּל־אֶחָ֗יו נָתַ֤תִּי לוֹ֙ לַעֲבָדִ֔ים וְדָגָ֥ן וְתִירֹ֖שׁ סְמַכְתִּ֑יו וּלְכָ֣ה אֵפ֔וֹא מָ֥ה אֶֽעֱשֶׂ֖ה בְּנִֽי׃
And Isaac answered and said unto Esau: ‘Behold, I have made him thy lord, and all his brethren have I given to him for servants; and with corn and wine have I sustained him; and what then shall I do for thee, my son?’
Zohar
"Behold, I have made him your lord...and what shall I do now for you, my son" (Beresheet 27:37). This means that there is no one present who gives consent, "What shall I do now for you, my son." He then blessed him in this world. He looked at his grade and said to him "and by your sword shall you live," for it is fitting of you to shed blood and wage wars. Therefore he said, "What shall I do now for you, my son".