Exodus 4:15-17

Amplified Bible

¹⁵ You must speak to him and put the words in his mouth; I, even I, will be with your mouth and with his mouth, and I will teach you what you are to do. ¹⁶ Moreover, he shall speak for you to the people; he will act as a mouthpiece for you, and you will be as God to him [telling him what I say to you]. ¹⁷ You shall take in your hand this staff, with which you shall perform the signs [the miracles which prove I sent you].”