1 Samuel 17:8-12

He stood and shouted to the ranks of Israel and said to them, “Why do you come out to draw up in battle formation? Am I not the Philistine, and you the servants of Saul? Choose a man as your representative and have him come down to me.

If he is able to fight me and kill me, then we will become your servants; but if I prevail against him and kill him, then you shall become our servants and serve us.”

Then the Philistine said, “I have defied the ranks of Israel this day! Give me a man, so that we may fight together.”

When Saul and all Israel heard these words of the Philistine, they were dismayed and very fearful.

Now David was the son of the Ephrathite of Bethlehem in Judah, the man whose name was Jesse, and he had eight sons. And Jesse was old in the days of Saul, advanced in years among men.