Exodus 4:10

4:10 Then Moses said to the Lord, “O my Lord, I am not an eloquent man, neither in the past nor since you have spoken to your servant, for I am slow of speech and slow of tongue.”

Exodus 4:14-16

4:14 Then the Lord became angry with Moses, and he said, “What about your brother Aaron the Levite? I know that he can speak very well. Moreover, he is coming to meet you, and when he sees you he will be glad in his heart.

4:15 “So you are to speak to him and put the words in his mouth. And as for me, I will be with your mouth and with his mouth, and I will teach you both what you must do. 4:16 He will speak for you to the people, and it will be as if he were your mouth and as if you were his God.