Functionally atheist? Of course not; I’m a Christian. If we are Christian, why do our lives seem to be so much like the lives of non-Christians? This is the very question that is on the minds of many non-Christians. What is going on?
First, our human nature has not and will not change: “That which is born of the flesh is flesh,” and “flesh and blood will not inherit the kingdom of God.” Like a drowning person, our human nature can never ever stop stressing about its fear of losing what it wants, no matter how much it has. Have you noticed how people who have so much of this world’s things are more nervous than others who have less? What if the things a drowning person has gathered to climb up on begin to sink?
Second, our regenerate soul never fears (except for that holy, healthy fear of God). Our soul does not worry or stress nor is it anxious or bothered – except by our own human nature. We are always honest about dependence on the living God who makes all things work together for good, who did not spare His own Son but gave Him up for us all and freely with Him gives us all things. All things are ours and we cannot die as eternal children of our heavenly Father.
Third – so why are some Christians functionally atheist? Anorexia of the soul. When our life is controlled by the appetites of our human nature; when we are constantly feeding on a culture of competition and emptiness – we are always going to be nervous, anxious, and afraid. But in as much as we feed our soul or at least begin to feed our soul, we have a very different experience. Not the experience of guilt and failure for not being more trusting but the experience of grace that forgives and atones for all our failings even as that grace fills us with the Words, will, and promises of God to us.
Functionally theist (Christian) is a function of who we are but also where we live and what we live on. The more we live in the kingdom of God, His Word, His sacraments, His constant providence for our life (sunshine, plant life, family, friends, our own heartbeat and respiration – all of nature and the super-natural) make theism functional, factual and fantastic in our lives.