Joshua 4:11-13

11and when all the people had finished crossing, the ark of the Lord and the priests crossed before the people. 121The sons of Reuben and the sons of Gad and the half-tribe of Manasseh crossed over in battle array before the sons of Israel, just as Moses had spoken to them; 13about 40,000 equipped for war, crossed for battle before the Lord to the desert plains of Jericho.