I never read Darwin’s Origin until I was around 60 years old. I attribute this both to the poverty of my education and to the widespread denial of the overwhelming significance of science for religious faith in the society in which I grew to be a man. I see, in people like John Polkinghorne and Arthur Peacocke, Ian Barbour and Paul Davies, holdovers from the age and time when it was thought, wrongly, that religion and science could continue on their own paths quite independently of each other as compatible ways of knowing about reality. It was still just possible to do that during the 1940s and 1950s, and on into the early 1960s of the last century, and for anyone who was brought up religious during those years it was still possible not to have encountered the religious conflict with science – which was, at the time, still a muted discussion taking place along the disputed borderlands between science and religion.
As a consequence, reading the Origin was a revelation to me. While I did not comprehend everything Darwin has to say in that great book — his frequent detailed geological descriptions simply flew over my head — it was obvious that what I did understand was in immediate conflict with religious faith as I understood it. I had already, by that time, begun to move away from any supernatural understanding of the objects of “faith”. I had never, to my certain knowledge, believed in an afterlife, but the central doctrines of Christianity still existed for me in a shadowland somewhere between belief and unbelief. I had tried, for a time, after becoming an Anglican in 1974, to hold to a fairly conservative anglo-catholicism, and even wrote a booklet about my conservative, catholic conception of Anglicanism which was published for some years by an ultra-conservative high church group in the dioceses of Nova Scotia and Fredericton (New Brunswick). This view of the church soon palled, as I found it more and more difficult to squeeze myself into spaces too small for someone trained as a philosopher to dwell in comfortably.
Nevertheless, I held onto vestiges of my anglo-catholicism as perhaps the only way to retain confidence in Christian theology as a discipline dealing with a presumptively objective reality. One of the problems with theology is that it deals with something for which there is no clear evidence, and therefore it is incredibly plastic. It’s very plasticity, however, implies that it is not about objective reality, since in order to be held to be objective there must be determinate and identifiable limits to what can reasonably be said, limits which, like property boundary markers, cannot be arbitrarily moved. That was, I suppose, a great deal of the attraction of catholic understandings of Christianity, because they offered, as the only legitimate way of thinking of specific religious doctrines, a framework composed of unalterable boundary conditions, established within Christian tradition, and surviving intact up to the present.
Of course, in order to achieve this point of view, an incredible amount of the history of the formation of Christian doctrine has to be ignored. One has to overlook the fact that Nicene Christianity took shape against the background of the most intense verbal and physical conflict. The faith “once delivered to the saints” is not only the outcome of furious and unrelenting debate, but could only have taken its historic form in the context of imperial authority. What gives Christian doctrine its appearance of objectivity is an illusion created by time and jealously guarded authority. In its inception it was an ideology designed to keep peace within a great empire. When this was seen for what it is, the unity of Christendom could not survive. Hence the warring creeds and sects that we have today, all of them calling themselves Christian, and many of them claiming to be not only the only true interpretation of the ancient texts and creeds, but also to be, by legitimate descent from the community gathered around Jesus, the same historical community. Some, like the Roman Catholic Church, the Orthodox churches of the East, the Anglican and Swedish churches, the old Catholic Church, and some others, perpetuate the illusion that there is an immediate physical connexion between their orders of ministry and the ministry of Christ and the twelve apostles. This physical connexion is understood to be of primary importance, for it supposedly legitimates their claim to be the “same” community to which Christ made the promise: “I am with you always, even to the end of the age.” (Matthew 28.20)
How could these palpably absurd claims have come to be made? And how it is possible that anyone should believe them now? It is just here that Darwin’s Origin comes in as a decisive refutation of Christian claims. The fact that we are evolved animals which, depending on sheer chance, happened to survive, and even to have become the most successful species ever to inhabit this planet, points irrefragably to the fact that we were not intended, and have no transcendent purpose in the world. Like ants and bees, butterflies and trees, we are entirely chance occurrences, and might never have been. This, along with the fact that the process of evolution is one of the most wasteful and diabolical ways of bringing sentient life into being, makes it clear, as nothing else could, that neither we, nor any other inhabitant of the earth, is the object of any special grace or favour. The belief that we are has to be held in the face of the reality of the massive suffering that the process of evolution itself requires in order to achieve its ends, and while some Christians blithely consider that evolution is God’s way of creating, and even have the temerity to point to the God of Job — whom the philosopher Tennessen, in his article, “A Masterpiece of Existential Blasphemy,” has justly called a being of incredibly crude primitivity, because in his epiphany Yahweh shows himself to be unworthy of an answer — as the inscrutable one, the radically incomphensible being who has in love prepared a place for us beyond our capacity to understand, the cruelty of evolution makes it clear that this is mere persiflage. Job, Tennessen says, sitting in misery in the midden of his village, covered with sores,
… has not been convinced (of any errors in his reasoning) about the justice of world order. He has, on the contrary, been reinforced in his beliefs. By capitulating in this manner [by repenting in dust and ashes], he inflicts the worst conceivable of indignities on the tyrant, Jehovah: that his opponent is not even worthy of a battle! 
All Job’s reasoning about God’s injustice and callous disregard for suffering still stands. God is just a Rumble-Dumble, as Tennessen says, a being of gross primitivity, childishly pleased with his power, unconcerned about suffering.
This, of course, as we all know, was Darwin’s conclusion too. He watched evolution in progress in the wasteful death and misery of his daughter Annie, and in the ichneumon wasp which laid its eggs in the living bodies of caterpillars. He might have seen it in the toad’s eye, as Matthew Cobb says over at Why Evolution is True:
There is something grotesque in suggesting that a being worthy of worship should create in this manner, and only desperation could lead believers to claim that this is the way their God creates. Of course, Pope Wojtyła believed that, in the process, God somehow allows for an ontological saltation, so that human beings have an additional spiritual particle called a soul, that distinguishes them from the rest of creation, and makes them fit for an eternal reward. The truth is, however, in my view, anyway, that Darwin puts an end to religious myths understood as more than fanciful stories. Perhaps it is still possible, as Keith Ward suggests in his book, God: A Guide for the Perplexed, to have a religion which makes no supernatural claims, but it is no longer possible to have a respectable belief system which posits eternal, all-powerful beings, who somehow control and intervene for good in the world. Darwin’s theory began a decisive move away from religious belief. This is, I think, undeniable. I also think it is inevitable and unstoppable. Religion must adapt or die.