1 Samuel 17:17-18

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.