(Bamidbar 33:52) "And you shall drive out all the inhabitants of the land from before you"
(Sotah 34a) While the Israelites were still in the Jordan, Yehoshua said to them: Know why you are crossing the Jordan – on condition that you drive out the inhabitants of the land from before you.
It is written in Sefer Yehoshua that the Cohanim carriers of the Aron stood in the Jordan River while Yehoshua stood on the west bank and the people stood on the east bank, while Yehoshua spoke the words which Moshe had commanded.
T.T. It appears that Yehoshua not only said the one verse, but the entire parsha (verses 53-56). He did this to fulfill the conditions of an oath (requires doubling of the conditions with first the positive and then the negative, plus requires saying the condition first and then the action to be done).
