1st Samuel 17:32

29 And David said, What have I done now? was it not only a word?

30 And turning away from him to one of the other men, he said the same words: and the people gave him the same answer.

31 And, hearing what David said, they gave Saul word of it: and he sent for him.

32 And David said to Saul, Let no man's heart become feeble because of him; I, your servant, will go out and have a fight with this Philistine.

33 And Saul said to David, You are not able to go out against this Philistine and have a fight with him: for you are only a boy, and he has been a man of war from his earliest days.

34 And David said to Saul, Your servant has been keeper of his father's sheep; and if a lion or a bear came and took a lamb from the flock,

35 I went out after him, and overcame him, and took it out of his mouth: and if, turning on me, he came at me, I took him by the hair and overcame him and put him to death.