Joshua 4:4-7, 19-24

So Joshua chose one man from each tribe. Then he called the twelve men together and said to them, “Go out into the river where the Ark of the LORD your God is. Each of you bring back one rock, one for each tribe of Israel, and carry it on your shoulder. They will be a sign among you. In the future your children will ask you, ‘What do these rocks mean?’ Tell them the water stopped flowing in the Jordan when the Ark of the Agreement with the LORD crossed the river. These rocks will always remind the Israelites of this.”

The people crossed the Jordan on the tenth day of the first month and camped at Gilgal, east of Jericho. They carried with them the twelve rocks taken from the Jordan, and Joshua set them up at Gilgal. Then he spoke to the Israelites: “In the future your children will ask you, ‘What do these rocks mean?’ Tell them, ‘Israel crossed the Jordan River on dry land. The LORD your God caused the water to stop flowing until you finished crossing it, just as the LORD did to the Red Sea. He stopped the water until we crossed it. The LORD did this so all people would know he has great power and so you would always respect the LORD your God.’ ”