Josh 4:1-14

After the entire nation had completed the crossing of the Jordan, the LORD said to Joshua: Choose twelve men from the people, one from each tribe, and command them, “Take up twelve stones from this spot in the Jordan riverbed where the priests have been standing. Carry them over with you, and place them where you are to stay tonight.”

Summoning the twelve men he had selected from among the Israelites, one from each tribe, Joshua said to them: “Go to the Jordan riverbed in front of the ark of the LORD, your God; lift to your shoulders one stone apiece, so that they will equal in number the tribes of the Israelites. In the future, these are to be a sign among you. When your children ask you, ‘What do these stones mean to you?’ you shall answer them, ‘The waters of the Jordan ceased to flow before the ark of the covenant of the LORD when it crossed the Jordan.’ Thus these stones are to serve as a perpetual memorial