And afterward he [Jacob] took His [God's] kingship upon himself, as it is said (Genesis 33:20): "And he set up there an altar, etc." And they [Israel] too took His kingship upon themselves, as it is said (Exodus 20:2): "I am the LORD your God." What did they say? They all answered with one mouth and said (Exodus 24:7): "All that the LORD has spoken we will do and we will obey." This is the meaning of (Job 22:28): "You shall decree a thing, and it shall be established for you."
Jacob Builds an Altar and Israel Accepts God's Kingship
Midrash Tanchuma Buber, Vayishlach 10:6
ואח"כ קיבל עליו מלכותו, שנאמר ויצב שם מזבח וגו' (בראשית לג כ), ואף הם קבלו עליהם מלכותו, שנאמר אנכי ה' אלהיך (שמות כ ב), מה אמרו ענו כולם בפה אחד ואמרו כל אשר דבר ה' נעשה ונשמע (שם כד יז), הוי ותגזר אומר ויקם לך.