Joshua 4:20 KJV

18And it came to pass, when the priests that bare the ark of the covenant of the LORD were come up out of the midst of Jordan, and the soles of the priests’ feet were lifted up unto the dry land, that the waters of Jordan returned unto their place, and flowed over all his banks, as they did before.

19And the people came up out of Jordan on the tenth day of the first month, and encamped in Gilgal, in the east border of Jericho.

20And those twelve stones, which they took out of Jordan, did Joshua pitch in Gilgal.

21And he spake unto the children of Israel, saying, When your children shall ask their fathers in time to come, saying, What mean these stones?

22Then ye shall let your children know, saying, Israel came over this Jordan on dry land.