‘ And they said to the people, “Pass on, and surround the city, and let the armed men pass on before the Ark of YHWH.”
Some manuscripts have ‘he'. So these words were either those of the priests or of Joshua himself. Either way they came from Joshua either directly or indirectly. Verse 8 would support ‘he', but as the more difficult reading ‘they' may well be correct.
The instruction was given to march round the city, surrounding it, the armed men leading the way followed by the Ark of YHWH. ‘The people' taking up the rear. The latter may possibly also have included women and children so that all would see the demonstration of the power of YHWH on their behalf, (but not necessarily. It may be that only armed men were involved, both leading the way and following. The Hebrew definite article regularly simply means ‘those I am talking about'). The armed men to the front may have been the Transjordanian troops (Joshua 4:12-13), ‘the people' the troops from the remainder, who would also have included older men who wanted to be involved.