1 Samuel 17:29-33

But David said, “What have I done now? Was it not just a question?”

Then he turned away from him to another and said the same thing; and the people replied with the same words as before. David Kills Goliath

When the words that David spoke were heard, they informed Saul, and he sent for him.

And David said to Saul, “May no one’s heart fail on account of him; your servant will go and fight this Philistine!”

But Saul said to David, “You are not able to go against this Philistine to fight him; for you are only a youth, while he has been a warrior since his youth.”