en_tn/exo/04/14.md

I will be with your mouth

This means God will give Moses the right words to speak. (See: rc://en/ta/man/translate/figs-idiom)

He will be your mouth

"He will say what you tell him to say" (See: rc://en/ta/man/translate/figs-metaphor)

you will be to him like me, God

Just as God told Moses what to say, Moses would tell Aaron what to say. (See: rc://en/ta/man/translate/figs-simile)