John Gill Commentary Joshua 6:9

"And the armed men went before the priests that blew the trumpets, and the rearward went after the ark, [the priests] blowing the trumpets as they went." — Joshua 6:9 (ASV)

And the armed men went before the priests that blew with the
trumpets
Whom Jarchi, Kimchi, and Abarbinel, interpret of Reuben and Gad, and the half tribe of Manasseh; that is, as many of them as Joshua took with him over Jordan; though rather all the armed men in the camp are meant; at least along with those mentioned went the standards of Judah and Ephraim:

and the rereward came after the ark ;
because the tribe of Dan was the rereward in journeying, (Numbers 2:31) ; hence the Targum paraphrases the words, ``and the tribe of the house of Dan went after the ark;'' and so both Jarchi and Kimchi interpret it: but rather the body of the people unarmed are designed; at least these were brought up by the standard of Dan; or otherwise no place in this procession is appointed for them, whose business it was to make the great shout on the seventh day with the rest:

[the priests] going on and blowing with the trumpets ;
the word "priests" is not in the text, but is rightly supplied; for, as Kimchi and Abarbinel observe, this is not said of the rereward, but of the priests, for they only bore and blew the trumpets; and so the Targum reads, ``the priests going on''