1st Samuel 17:35

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.

36 Your servant has overcome lion and bear: and the fate of this Philistine, who is without circumcision, will be like theirs, seeing that he has put shame on the armies of the living God.

37 And David said, The Lord, who kept me safe from the grip of the lion and the bear, will be my saviour from the hands of this Philistine. And Saul said to David, Go! and may the Lord be with you.

38 Then Saul gave David his clothing of war, and put a head-dress of brass on his head and had him clothed with a coat of metal.