How we can know God exists – and why it matters

Is God optional? You know – is it a take it or leave it kind of matter whether or not God is there? Our culture certainly thinks it is. Most people today seem to think that God is something that you might reasonably believe in or not, a matter of faith, not reason or logic. Douglas Adams in The Hitchhiker’s Guide to the Galaxy famously had God disappear in a ‘puff of logic’ for inadvertently proving that he exists by creating the Babel Fish. For, says Man, ‘it’s a dead giveaway isn’t it?’ And if God has proven that he exists, then, the argument runs, he has left no room for faith, without which he is nothing. This idea of needing to leave room for faith goes back to at least Immanuel Kant in the 18th century, who advanced the then radical idea that God’s existence could not be demonstrated by pure reason but required a step of faith beyond what ordinary human reason could show.

Such an idea was radical then because up till that time most thinkers – and not only Christians – had held that God’s existence could be known as certain fact because it was logically necessary to explain the universe as we know it. The Greek pre-Christian philosophers Plato and Aristotle, for instance, had argued that God must exist because there must be an absolute reality that stands behind the shifting forms of nature, a Being in whom subsists the eternal intelligible realm of perfect order and goodness, a first cause and a pure form. Here, for example, is Plato, in a passage strikingly redolent of scripture:

God, as the old tradition declares, holding in his hand the beginning, middle, and end of all that is, travels according to his nature in a straight line towards the accomplishment of his end. Justice always accompanies him, and is the punisher of those who fall short of the divine law. … Every man ought to make up his mind that he will be one of the followers of God… And he who would be dear to God must, as far as is possible, be like him and such as he is.

Modern thinkers, including many scientists, have further argued that God is necessary to explain the universe because without a divine designer it is impossible to account for how finely tuned the laws of nature are for the emergence of life and, most pertinently, humankind – a fine-tuning that even non-theist scientists like Stephen Hawking acknowledge. Many also point out that a scientific materialist account of nature has yet to come up with any plausible way of explaining the existence of things like consciousness, free will and morality – phenomena basic to our human experience, and notoriously tricky to squeeze into any materialist world view.

This idea that human beings can, through the use of their ordinary rational faculties, be confident of the existence of their Creator is one endorsed in scripture. Psalm 19 declares that ‘the heavens declare the glory of God’, and Paul in Romans 1:18-20 argues that people are ‘without excuse’ for their sinful neglect of God, since ‘what can be known about God is plain to them, because God has shown it to them. Ever since the creation of the world his eternal power and divine nature, invisible though they are, have been understood and seen through the things he has made.’ James points out that even the demons believe there is one God – ‘and shudder’ (James 2:19).

Yet despite this unmistakable endorsement in scripture, and a long and distinguished history of Christian thinkers engaging with natural theology, many Christians in the last century or so have bought into what we might call the Immanuel Kant-Douglas Adams way of thinking. Karl Barth, for instance, the eminent early 20th century Reformed theologian, uttered a famous ‘Nein!’ to natural theology. Although his more carefully stated position came with nuances not always appreciated by those who follow him, there can be little doubt that large parts of the Reformed and Protestant tradition in which he was such a major figure have jettisoned any real confidence in the theological insights of natural reason. This mirrors similar developments in the wider culture, as the gap between the outlooks of Christians and those without faith has widened into what can only be described as a yawning gulf. Yet for Christians the logic that animates natural theology has never changed.

The crucial distinction on which the possibility of natural theology rests is that between general revelation and special revelation. Special revelation is what God has revealed of himself and his purposes in human history and which, Christians believe, has been authoritatively captured in the words of Holy Scripture. General revelation is what God has made generally available about his nature and purposes to all people through rational reflection on, to use Paul’s words, ‘the things he has made’. Since from a Christian point of view both types of revelation reveal truths about God and his creation, the two cannot be in conflict, and if they appear to be then the conflict needs to be resolved, by revisiting either the interpretation of scripture or the meaning and accuracy of the empirical data.

A vexed question here is whether general revelation can save a person. Clearly salvation comes only through Jesus Christ, his atoning death and life-giving resurrection. And all those who repent and put their trust in Jesus receive forgiveness of sins and life in his name. The question is whether it is only people who have the benefit of special revelation in the form of the Gospel who can share in this salvation, or whether God makes provision for people who never hear the Gospel but respond positively to such revelation as they receive. Cornelius’ vision in Acts 10, in which an angel assures him that his prayers have been heard and his alms ‘remembered before God’, and Peter’s subsequent declaration that ‘God shows no partiality,’ and ‘in every nation anyone who fears him and does what is right is acceptable to him’ (Acts 10:31-5) suggest there is scope in God’s grace for salvation in Christ via general revelation, at least for those who have had no opportunity to hear the Gospel. This may be supported by Paul’s teaching that God, ‘who is not far from each one of us,’ has caused people to search for him ‘and perhaps grope for him and find him’ (Acts 17:27), while in his divine forbearance he has ‘passed over the sins previously committed’ (Romans 3:25) and ‘overlooked the times of human ignorance’ (Acts 17:30). And of course there is the status of Abraham and others of God’s people before Christ. But despite these tantalising intimations we have to admit there is no clear teaching on this, and it seems God is content to give us only hints about how he will handle those whom the Gospel has not reached, while we are to get on with preaching the Gospel.

But in any case, one thing we can say with confidence is that general revelation serves as an important precursor to the Gospel in human culture, preparing human minds and hearts to receive the message of salvation in Christ. Another key aspect of general revelation is that it is the basis on which all people can come to a shared understanding of the meaning and significance of human life, on a level sufficient at least for civic friendship and mutual endeavour.

In this connection, let us note that general revelation shows us not only God’s existence but also some of his purposes in creation, many of which we encounter as the natural law. The part of this law governing rational human conduct we know of as the rational moral law. In Romans 2:14-16, Paul explains how God has written his law on the hearts of all people, and how their consciences bear witness to this revelation in and through their nature. Yes, humanity is fallen, and human reason is wounded and prone to error and bias. But even in this fallen, wounded state our reason can, with sufficient care, be expected to attain to many correct conclusions about God and his purposes, his laws.

Time permits me to give only a couple of examples here to illustrate how this process works, though the examples are perhaps the most pertinent at the present day. The first is the key insight that human beings bear the image of God. The image of God appears in Genesis 1:26-7, at the creation of humanity, so it is clearly part of special revelation. But it is also found outside scripture, in a number of ancient writers, so we can conclude it is also part of the general revelation. It appears, for instance, in Plato, where he contends that the rational soul possessed by humans uniquely bears the imprint of the divine nature. And it is a prominent theme in Stoic philosophy, with the Roman statesman Cicero writing of human beings as having ‘what can truly be called a lineage, origin, or stock in common’ with the divine, so that ‘the same moral excellence resides in man and in God, and in no other species besides.’ The Stoics regarded the divine Reason, or Logos, to govern the world – an idea we find picked up in the Gospel of John, where it is identified with Christ – and humanity to be, within nature, the supreme partakers in that divine Reason.

How, without scripture, do these thinkers know that humanity so closely resembles the divine? It is because human beings possess a rational mind, a mind which it is evident from the order of nature must be of the same kind of thing possessed by the Creator of the cosmos, by which he conceived and ordered his creation. This is why human beings are the only part of nature which can know of God and know God and understand his ways insofar as he has revealed them to us.

A second very topical example is the recognition that humanity is created as a sexed creature, male and female, and that this basic duality is fundamental to our nature as God has designed it. Important moral principles arise from this sexually differentiated human condition, firstly out of basic respect for the divine design, and secondly because of the weak and dependent condition of the human offspring that result from the sexual union of male and female. There is a basic moral requirement, for instance, to safeguard the beginnings of human life in its extreme weakness and dependence, and also to ensure that each new human being receives the best opportunity to succeed in life through the attentive care of both its mother and father. The main outworking of these observations is the promotion and protection of the institution of marriage.

It is clear that both of these key ethical principles – the significance of the image of God and the sanctity of marriage – are being heavily eroded in our culture, whether through aggressive agendas to legitimise the destruction of dependent human life, be it very young, very old or disabled, or the near continual assaults on the sanctity of the married family. But should this really be any surprise when God himself has been side-lined and presumed to be irrelevant in modern society? How, after all, can human beings be recognised as made in the image of God if God’s existence is regarded as highly questionable? Or how can God’s design of male and female and his prescription for the best context for welcoming new human life be honoured if human beings are not thought to bear any divine design at all? Without God it is little wonder that individual subjective experience has begun to take precedence over the Creator’s purposes.

Abandoning God has consequences. That applies not only on an individual level but also on a social level. Non-believers cannot know God like believers know God, as their heavenly Father and their Saviour in Christ. But they can know about God. They can know what Plato and Cicero knew: that without God there is no foundation for the truth about humanity and our place in the world and how we ought ideally to be. For on what else, besides the transcendent design of our Creator, could human identity and ideals be objectively grounded? What is left of us if we are merely the incidental by-product of an unintended process of gene replication, emerging purposelessly from the slime that happened to have accumulated on some lonely rock among the countless stars?

Western culture has been moving towards being post-Christian and post-God for a long time now – at least since the French Revolution of 1789. Atheism, along with its more diffident cousin agnosticism, have been growing steadily since then in social reach and cultural penetration, while the general revelation of God and his purposes has been progressively side-lined. God is dead, declared Nietzsche, and many have nodded in agreement. The world thinks it can do without God and his purposes, that it can function just fine with a postmodern, post-Christian, post-God vision centred on the subjective experience of the sovereign individual. But as Christians we know that despite all its promise of liberation from the shackles of history and nature that is a recipe only for disorder, disillusionment and despair. One of the great gifts that we as Christians bring as we engage with our society is not only the special grace of the Gospel of salvation, but also a fresh clarity about the common grace that is ours to share as the human race. But is it a gift that our society will ever be pleased to receive again? The future, of course, is in God’s hands. All we can do is keep on offering this gift to those around us, holding it out to a world set on going its own way. In doing this we aspire to that perfection that Jesus calls us to in imitation of our heavenly Father – the God who ‘makes his sun rise on the evil and on the good, and sends rain on the righteous and on the unrighteous’ (Matthew 5:45-8).

This post originated as a presentation at the Festival of Theology in October and was first published on Ian Paul’s Psephizo blog.


2 thoughts on “How we can know God exists – and why it matters

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  1. Dear Will: it is at the point of the connection between the physical and the metaphysical that most issues seem to arise. This connection point might also be typified as that between the quantitative and the qualitative (Oakeshott) and in mathematics between the real and imaginary (QM). However we characterise this junction, it is in questions over how it works that there are issues. You above have it as ‘because humans are rational and can see order ….’. So can dolphins and monkeys and recent research has it even crows can. Much of Creation is disorderly. In fact we distinguish the manmade from the natural precisely at the interface between what is ordered and what isn’t. If Creation truly is ordered as a fundamental attribute, as eg McGrath would have us believe, it should be possible logically to understand the Orderer from the order of His Creation. Except it isn’t and we can’t. Genesis 1 in its language has the Creator forging something fit for purpose, not as creating something ordered. We must look elsewhere I believe for an explanation of how Natural Theology functions. Kind Regards, timW


  2. Isn’t the point though that natural theology in a fallen world world won’t be clear as we would like particularly when nature is red in tooth and claw but still there is a cosmos, not chaos and there is irrefutable and inexplicable ‘us’, which the God hypothesis explains better than the alternatives. And then the special revelation, the Logos, makes it adequately clear.


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