John Gill Commentary Judges 2:21

"I also will not henceforth drive out any from before them of the nations that Joshua left when he died;" — Judges 2:21 (ASV)

I also henceforth will not drive out and from before them ,
&c.] At least not as yet, not very soon nor hastily, as in (Judges 2:23) ;

of the nations which Joshua left when he died ;
that is, unsubdued; which was owing either to the infirmities of old age coming upon him, which made him incapable of engaging further in war with the Canaanites; or to the sloth and indolence of the people, being weary of war, and not caring to prosecute it; or to want of men to cultivate any more land, and people other cities, than what they were possessed of;

and chiefly this was owing to the providence of God, who had an end to answer hereby, as follows.