Joshua 4:2-5

4:2 “Select for yourselves twelve men from the people, one per tribe. 4:3 Instruct them, ‘Pick up twelve stones from the middle of the Jordan, from the very place where the priests stand firmly, and carry them over with you and put them in the place where you camp tonight.’”

4:4 Joshua summoned the twelve men he had appointed from the Israelites, one per tribe. 4:5 Joshua told them, “Go in front of the ark of the Lord your God to the middle of the Jordan. Each of you is to put a stone on his shoulder, according to the number of the Israelite tribes.