A long time. Seven years, as appears from chap. xiv. 10., (Challoner) where Caleb informs us that he was 85 years old. He was 40 when he went to explore the country, and 38 years were spent in the wilderness. God was pleased to allow the Chanaanites time to repent, and he would not render the country desolate all at once, lest wild beasts should overrun it, Exodus xxiii. 19., and Wisdom xii. 10. (Calmet)