1 Samuel 17:12-18

12Now David was the son of an Ephrathite named Jesse, who was from Bethlehem in Judah. Jesse had eight sons, and in Saul’s time he was very old. 13Jesse’s three oldest sons had followed Saul to the war: The firstborn was Eliab; the second, Abinadab; and the third, Shammah. 14David was the youngest. The three oldest followed Saul,

15but David went back and forth from Saul to tend his father’s sheep at Bethlehem.

16For forty days the Philistine came forward every morning and evening and took his stand. 17Now Jesse said to his son David, “Take this ephah That is, probably about 36 pounds or about 16 kilograms of roasted grain and these ten loaves of bread for your brothers and hurry to their camp. 18Take along these ten cheeses to the commander of their unit. See how your brothers are and bring back some assurance Or some token; or some pledge of spoils from them.