Shemot Rabbah 3:15שמות רבה ג׳:ט״ו
“The Lord said to him: Who makes a man’s mouth?” He [God] said to him: ‘If you are not a man of words do not be concerned; haven’t I created all the mouths in the world, and I rendered mute whomever I wished, and [likewise determined who is] deaf and blind, and sighted and hearing? Had I wished for you to be a man of words, so would you be. Rather, I wish to perform a miracle with you. When you speak, your words will be exact, as I will be with your mouth.’ That is what is written: “And I will be with your mouth.” What is “and teach you [vehoreitikha]”? Rabbi Abbahu said: I will shoot [moreh] My words into your mouth like an arrow, as it states: “Or will be shot [yaro yiyareh]” (Exodus 19:13). Rabbi Simon says: I will create you into a new being, as it is stated: “The woman conceived [vatahar] [and bore a son]” (Exodus 2:2).
Haamek Davar on Exodus 4:11:1העמק דבר על שמות ד׳:י״א:א׳
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