1 Samuel 17:32-34

And David said to Saul, “Let no man’s heart fail because of him. Your servant will go and fight with this Philistine.” And Saul said to David, “You are not able to go against this Philistine to fight with him, for you are but a youth, and he has been a man of war from his youth.” But David said to Saul, “Your servant used to keep sheep for his father. And when there came a lion, or a bear, and took a lamb from the flock