Exodus 4:16

And he shall speak for you to the people, and he shall be your mouth, and you shall be for him in things pertaining to God.

And he shall be thy spokesman unto the people: and he shall be, even he shall be to thee instead of a mouth, and thou shalt be to him instead of God.

He will be your spokesman to the people. It will happen that he will be to you a mouth, and you will be to him as God.