Шмот 6:26 Мидраш: Mekhilta DeRabbi Yishmael, Esther Rabbah, Bereshit Rabbah & Ein Yaakov (Glick Edition)

(Exodus 12:1) "And the L–rd spoke to Moses and to Aaron in the land of Egypt, saying": I might think that both Aaron and Moses were being addressed; it is, therefore, written (Exodus 6:28) "And it was on the day that the L–rd spoke to Moses in the land of Egypt": Only Moses was being addressed and not Aaron. If so, why is it written "to Moses and to Aaron"? We are hereby taught that just as Moses was "included" in the words (i.e., by their being spoken to him), so, Aaron was included in the words (i.e., by his "overhearing" them). And why did He not speak (directly) to him? In deference to Moses. We find Aaron, then, to be excluded from all the (direct) addresses in the Torah except for three (Leviticus 10:8, Numbers 18:1, Numbers 18:8), where it is impossible (to understand otherwise).

“It was during the days of Aḥashverosh; that [hu] Aḥashverosh who reigned from India to Kush, one hundred and twenty-seven provinces” (Esther 1:1). Hu [appears] five [times] for evil, and five for good. Five for evil: “He [hu] was a mighty hunter”⁴Nimrod. (Genesis 10:9); “he is [hu] Esau, father of Edom” (Genesis 36:43); “this is [hu] Datan and Aviram” (Numbers 26:9); “he is [hu] King Aḥaz” (II Chronicles 28:22); “that [hu] Aḥashverosh” (Esther 1:1). Five for good: “Abram, he is [hu] Abraham” (I Chronicles 1:27); “that [hu] Aaron and Moses…that [hu] Moses and Aaron” (Exodus 6:26–27); “David was [hu] the youngest” (I Samuel 17:14); “he [hu], Yeḥizhiyahu” (II Chronicles 32:30); “he [hu], Ezra, came up from Babylon” (Ezra 7:6). Rabbi Berekhya said in the name of the Rabbis from there: We have one that is better than all of them: “He is [hu] the Lord our God; His judgments are throughout the land” (Psalms 105:7), whose attribute of mercy is forever.

Variantly: "to Moses and to Aaron": I might think that the one who takes precedence in the verse takes precedence in the act. It is, therefore, written (Exodus 6:26) "It is Aaron and Moses" — Both are equal.