I was getting ready to go to church and the Lord showed me this.

Scripture:

Numbers 14:27 "How long shall I bear with this evil congregation, which murmur against me? I have heard the murmurings of the children of Israel, which they murmur against me."

Israel kept complaining about what they had left in Egypt (the world) and that God had brought them out into the wilderness to die. The wilderness was used by God to remove a generation of unbelieving, hard hearted and a selfish people who murmured against Him.
Israel's murmuring cost them their lives and forty years in the wilderness.
Until that generation ( they had been saved and under the blood ) had passed away and a new generation had come ( A total reliance on God ).

God uses a wilderness in our lives to cleanse us and bring us closer to Him. As we rely more on God than ourselves to supply our needs.
In our own lives we try to do everything ourselves and the more we try the harder things become. The longer we leave God out the harder it becomes to submit to Him.
In my own life I am guilty of murmuring against God. I have always had a fear of living in poverty. Never having enough to support myself ( Israel wanting to go back to Egypt where they had food yet in slavery). I have to give it over to the Lord. As I know that He can and does supply all my needs ( God had sent manna from heaven and water from rocks for Israel yet they complained ).

So it is with us. Until we stop complaining and learn to trust in the Lord. We will still be out there wandering in the wilderness and not crossing over into the land of milk and honey.
Even though we are saved and under the Blood of Jesus we still come under the attack of the enemy for wanting things of Egypt.

Stand firm with the whole amour of God ( Ephesians 6 : 12-18 )