The passuk says Miriam asked the daughter of Pharaoh, “Shall I go and call for you a wet-nurse from the Jewish women and she will nurse the young boy for you?” Rashi explains that the daughter of Pharaoh tried to have Moshe nurse from many Egyptian women, however he didn’t nurse. Since he would speak to the Shechina it was inappropriate for him to nurse from them.
The Rama brings that the milk of a Jewish lady and an Egyptian lady are the same- meaning one can nurse from either of them. However, if one has an option to nurse from a Jewish woman he shouldn’t nurse from an Egyptian woman. This is because the milk of a non-Jewish woman is metamtaim the heart. It stuffs up the child’s heart and it brings forth bad nature in the child.
The Darchei Moshe brings from the Rashba that it is a midas chasidus not to nurse from a non Jew. The nature of Yisrael is to be rachmanim and bayshanim, therefore their milk is like them, and it brings to a good nature. However a non-Jewish woman isn’t, and therefore her milk will bring to bad midos. The Hagahos brings to warn Jewish women who nurse not to eat nevailos and chazir, even when sick and in need of such food.
The Biyur haGra says the Rama learned this from Moshe Rabeinu. He refused to nurse from the Egyptian was because he would speak to the Shechina.
Rav Yaakov Kaminetzky, zatzal, asked how is Moshe the source for this ruling? Is everyone going to speak to the Shechina that they shouldn’t nurse from a non Jewish woman?
Rav Yaakov says we see here a great lesson in chinuch. For every little child there is the possibility and hope for him to speak with the Shechina. Therefore his upbringing needs to be with the highest level of “he will speak with the Shechina.” When one chooses chinuch, one needs to choose with special tahara and kedusha for the most proper chinuch possible for his child.
May Hashem help us be mechanech with tahara and kedusha and strive towards the highest levels.