Parashas Shemos · Passuk 2:7
Chabad.org — English translation + Rashi
Torah Temimah points to Sotah 12b (verified).
Sefaria — Exodus 2:7
Sefaria — Sotah 12b
E-Daf — Sotah 12b
English: “A wet-nurse from the Hebrew women” — why specifically from the Hebrew women? This teaches that they passed him among all the Egyptian women to nurse and he would not nurse.
On the daf / in context: See the cited source for the full section.
Custom
Chazal teach that Moshe refused all Egyptian wet-nurses, preserving the purity of the mouth that would later speak with God.