They were unable to enter his rest because of unbelief. Therefore, while the promise of entering his rest still stands, let us fear lest any of you should seem to have failed to reach it. Hebrews 3:19-4:1
I remember being very weary of the life I was living. An endless cycle of failure, asking forgiveness (but not really meaning it) and repeated failure meant many sleepless nights. It meant looking in the mirror and not liking what I saw. I was weary. I needed to enter the rest of God. I wanted the peace of God.
This rest however, comes at a cost. I wanted to be free and I wanted to know rest, but I would not do anything to rid my life of that which was causing the turmoil. I would not stop following the appetites of my flesh nature. I would not stop pursuing self. This is the essence of the unbelief that kept the Israelites out of the Promised Land. They believed in God in their minds, but they did not obey him in their actions. They offered lip service without actually following him.
The rest that God provides does not mean we will live a problem-free life. We will still face challenges. The rest that God provides is a clean conscience and a sweet communion with him. Living in right relation with him is a peace like no other. Running from him is a misery like no other.
If we long for the rest that God provides when we are in right relation to him, we have to do whatever it takes to follow him. We do not get to enter rest of God while pursuing the life of self.