1 Samuel 17:12-17

12Now David was the son of that Ephrathite of Beth-lehem-judah, whose name was Jesse; and he had eight sons: and the man was an old man in the days of Saul, stricken in years among men. 13And the three eldest sons of Jesse had gone after Saul to the battle: and the names of his three sons that went to the battle were Eliab the first-born, and next unto him Abinadab, and the third Shammah. 14And David was the youngest; and the three eldest followed Saul. 15Now David went to and fro from Saul to feed his father’s sheep at Beth-lehem. 16And the Philistine drew near morning and evening, and presented himself forty days.

17And Jesse said unto David his son, Take now for thy brethren an ephah of this parched grain, and these ten loaves, and carry them quickly to the camp to thy brethren;