1 Samuel 17:12-15

Now David was the son of that Ephrathite of Beth-lehem-judah, whose name was Jesse; and he had eight sons: and the man went among men for an old man in the days of Saul. And the three eldest sons of Jesse went and followed Saul to the battle: and the names of his three sons that went to the battle were Eliab the firstborn, and next unto him Abinadab, and the third Shammah. And David was the youngest: and the three eldest followed Saul. But David went and returned from Saul to feed his father's sheep at Beth-lehem.