‘ For the priests who bore the Ark stood in the midst of Jordan, until everything was finished that YHWH commanded Joshua to speak to the people, according to all that Moses commanded Joshua, and the people hurried and passed over.'
Note here the twofold emphasis. Firstly that the people obeyed YHWH in everything that He had commanded through Joshua, and secondly that Joshua behaved uprightly in the way that Moses had commanded him, by obeying YHWH in accordance with the laws of Moses, turning neither to the right hand or to the left (Joshua 1:7 compare Deuteronomy 31:7). In all that Joshua did Moses was behind him and was his mentor.
Note also that the priests stood firmly in the midst of the Jordan with the Ark of the covenant of YHWH until everything was completed. For all would believe that were the Ark to leave the river the waters would flow again. It was only YHWH Who was holding them back.
“And the people hurried and passed over.” There were many of them and many possessions. As hour by hour passed they swarmed over, moving quickly so that those behind might also be able to follow.