For Israel to receive the promise land they needed to participate in God's plan. It was easy for God to bring Israel out of Egypt, but it was a bit of a challenge to get Egypt out of Israel.  Israel was free on the outside, but still a slave on the inside.  Their perspective prevented them from seeing God correctly.  This ended up disqualifying the very people God had qualified. 

God wants his will to be done on earth just like it is in heaven.  We are a big part of that plan.  In order to manifest the things on earth that Jesus accomplished in the spirit requires we take new territory.  And taking new territory requires a new mindset.