Jeremiah thinks he is too young and that people won't listen to him. God tells him that He will give him the words to say.
1:5 “Before I formed you in the womb I knew you,
before you were born I set you apart;
I appointed you as a prophet to the nations.”
6 “Alas, Sovereign LORD,” I said, “I do not know how to speak; I am too young.”
7 But the LORD said to me, “Do not say, ‘I am too young.’ You must go to everyone I send you to and say whatever I command you.
8 Do not be afraid of them, for I am with you and will rescue you,” declares the LORD.