While in Egypt they provided for themselves. God's power was highlighted in the wilderness, while man was lifted up as a god in the case of Egypt's Pharaoh. The Exodus was a time of testing, but the captivity was a time of comfort. We often seek to return to that Egypt in our lives to our detriment. This act of looking back reminds of the hand on the plow.
Victory only comes in the wilderness.
These thing have I spoken unto you, that in me you might have peace. He did not accomplish this through armies, or demonstrations, or miracles. He defeated the world by being spent. He died on the cross and the world was handed its greatest defeat. All we need to do is to read Isaiah 53 on a daily basis to drive home the idea of victory through suffering.