1 Samuel 17:16

14David was the youngest; and the three oldest followed Saul.

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

16The Philistine came near morning and evening, and presented himself forty days.

17Jesse said to David his son, “Now take for your brothers an ephah of this parched grain and these ten loaves, and carry them quickly to the camp to your brothers;

18and bring these ten cheeses to the captain of their thousand; and see how your brothers are doing, and bring back news.”