Judges 2:21-23

MLV(i) 21 I also will not hereafter drive out any from before them of the nations that Joshua left when he died, 22 that by them I may prove Israel, whether they will keep the way of Jehovah to walk in it, as their fathers kept it, or not.
23 So Jehovah left those nations, without driving them out quickly. Neither did he deliver them into the hand of Joshua.