Parashas Bo · Passuk 12:3
Chabad.org — English translation + Rashi
Torah Temimah points to Mechilta (verified).
Sefaria — Exodus 12:3
Sefaria — Mechilta
English: “Speak” — Rabbi Yishmael said: But it already says “And you, speak to the children of Yisrael”; rather, because Moshe would show honor to Aharon and Aharon would show honor to Moshe, the speech issued from between them as if both were speaking.
In context: See the cited source for the full section.
Derash on the verse (Mekhilta) — not a formal named middah of the 13.
Moshe and Aharon shared the address to Yisrael through mutual honor.