Joshua 4:12
“And the children of Reuben, and the children of Gad, and half the tribe of Manasseh, passed over armed before the children of Israel, as Moses spake unto them:”
For the priests which bare the ark stood in the midst of Jordan, until every thing was finished that the Lord commanded Joshua to speak unto the people, according to all that Moses commanded Joshua: and the people hasted and passed over.
And it came to pass, when all the people were clean passed over, that the ark of the Lord passed over, and the priests, in the presence of the people.
And the children of Reuben, and the children of Gad, and half the tribe of Manasseh, passed over armed before the children of Israel, as Moses spake unto them:
About forty thousand prepared for war passed over before the Lord unto battle, to the plains of Jericho.
On that day the Lord magnified Joshua in the sight of all Israel; and they feared him, as they feared Moses, all the days of his life.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“But we ourselves will go ready armed before the children of Israel, until we have brought them unto their place: and our little ones shall dwell in the fenced cities because of the inhabitants of the land.”
“And Moses said unto them, If ye will do this thing, if ye will go armed before the Lord to war,”
“But thy servants will pass over, every man armed for war, before the Lord to battle, as my lord saith.”
“And I commanded you at that time, saying, The Lord your God hath given you this land to possess it: ye shall pass over armed before your brethren the children of Israel, all that are meet for the war.”
“But when ye go over Jordan, and dwell in the land which the Lord your God giveth you to inherit, and when he giveth you rest from all your enemies round about, so that ye dwell in safety;”