I Samuel 17:5-15

He had a bronze helmet on his head, and he was armed with a coat of mail, and the weight of the coat was five thousand shekels of bronze. And he had bronze armor on his legs and a bronze javelin between his shoulders. Now the staff of his spear was like a weaver’s beam, and his iron spearhead weighed six hundred shekels; and a shield-bearer went before him. Then he stood and cried out to the armies of Israel, and said to them, “Why have you come out to line up for battle? Am I not a Philistine, and you the servants of Saul? Choose a man for yourselves, and let him come down to me. If he is able to fight with me and kill me, then we will be your servants. But if I prevail against him and kill him, then you shall be our servants and serve us.” And the Philistine said, “I defy the armies of Israel this day; give me a man, that we may fight together.” When Saul and all Israel heard these words of the Philistine, they were dismayed and greatly afraid. Now David was the son of that Ephrathite of Bethlehem Judah, whose name was Jesse, and who had eight sons. And the man was old, advanced in years, in the days of Saul. The three oldest sons of Jesse had gone to follow Saul to the battle. The names of his three sons who went to the battle were Eliab the firstborn, next to him Abinadab, and the third Shammah. David was the youngest. And the three oldest followed Saul. But David occasionally went and returned from Saul to feed his father’s sheep at Bethlehem.