Joshua 4:20-23

Those twelve stones which they had taken from the Jordan, Joshua set up at Gilgal. He said to the sons of Israel, “When your children ask their fathers in time to come, saying, ‘What are these stones?’ then you shall inform your children, saying, ‘Israel crossed this Jordan on dry ground.’ For the LORD your God dried up the waters of the Jordan before you until you had crossed, just as the LORD your God had done to the Red Sea, which He dried up before us until we had crossed