And he shall be your spokesman unto the people: and he shall be, even he shall be to you instead of a mouth, and you shall be to him instead of God.
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Augustine of Hippo
AD 430
One should notice that when Moses is sent to the people, God does not say to him, “Behold, I gave you as a god to the people, and your brother will be your prophet,” but he says, “[Your brother] will speak to the people for you.” For Scripture had said, “He will be your mouth, and you will be to him as God.” It did not say, “You are god to him.” But to Pharaoh Moses is said to be given as god, and according to analogy, Aaron is a prophet of Moses, but to Pharaoh. Here it is suggested to us that prophets of God say what they hear from him. A prophet of God is nothing but one who speaks the words of God to men—those who either cannot hear God or do not deserve to.
To God. Hebrew, "thou shalt be to him in the place of God. "He shall hear and obey thee, explaining to the people the instructions thou shalt give him. I have established thee the god of Pharao, and Aaron shall be thy prophet, chap. vii. 1. (Calmet)
I will address myself immediately to thee. (Tirinus)