There is no room for pessimism in Christianity because the basic Christian attitude is one of optimism.  God is in control; He will cure the evils of the world and answer our questions in ways beyond our imagining.  We are citizens of the New Jerusalem and as such the difficulties and pains we experience in life have meaning and purpose. They are part of our Christian witness, part of the Christian witness of the ages that, Jesus wins.  No matter what we are facing in our lives; no matter our fears for our loved ones or our questions for the future, we can be positive.  We are citizens of the New Jerusalem; our optimism colours every action of our lives.  Sin will never win the final battle.  Evil, no matter how powerful it may seem, will never conquer the world or us.  Jesus Christ has won.  God is in control.  What is the New Jerusalem that will someday rule the world?  It is not a physical place; the New Jerusalem is the Kingdom of God among us where all will be equal, all made new in Jesus.  All are welcomed as its citizens.

 …in Jesus begun, in heaven made whole!