Exodus 4:10-12

10Then Moses said to the Lord, ‘My Lord, I cannot speak well. I speak slowly and I speak with difficulty. I never could speak well. And even now, when you have spoken to me, I still cannot speak well.’

11Then the Lord said to Moses, ‘Who has made human mouths? Who makes a person that cannot speak? Who makes a person that cannot hear? Who makes a person who can see, or who cannot see? It is I, the Lord God!

12Now go! I will help you to speak well. I will teach you what you must say.’