Joshua 8:32-33

32And there, in the presence of the sons of Israel, Joshua wrote on the stones a copy of the Law of Moses which Moses had written.

33All Israel, the stranger as well as the native born [among them], with their elders and officers and their judges, stood on either side of the ark before the Levitical priests who carried the ark of the covenant of the Lord. Half of them stood in front of Mount Gerizim and half of them in front of Mount Ebal, just as Moses the servant of the Lord had commanded at first to bless the people of Israel.