This question is important for the Church today and on the face of it seems to be fairly straightforward. But my professional training is in philosophy, and true to the stereotype of philosophers, the first thing I’d like to do is complicate the question by analyzing the terms.

What is the question?

“Can” Christians believe in evolution? Well, a lot of them say they do, so in that sense the answer is “yes they can.” But we’re really interested in whether they should. That is, are there fundamental tensions or even contradictions between Christianity and evolution such that people cannot consistently adhere to both?

Next, can “Christians” believe in evolution? I won’t get into the business of who is and isn’t a genuine Christian here, but of course the range of Christian positions we admit will have an effect on how we answer the question. For this essay I’ll limit that range to Christians who take the Bible seriously as authoritative and inspired by God.

Now we get to the trickier parts of the question: “believe in” and “evolution”. Both of these terms can be taken in different ways. To me “believe in” sounds more like the profession of faith than the acceptance of some scientific data. I believe in Jesus; I don’t believe in photosynthesis in that sense. And “evolution” — especially when it is coupled with “believe in” — is too often taken as an all-encompassing worldview. The worldview of evolution (or evolutionism) generally involves commitments to naturalism and to human existence being accidental and purposeless. So if our question means “Should Bible-believing Christians have faith in evolutionism?” then I think the obvious answer is no.

But if instead the question is understood to mean “Should Bible-believing Christians accept the scientific theory of evolution?”, my answer is yes. I think evolution as a scientific theory is true, and since all truth is God’s truth, it shouldn’t cause a problem for true Christian faith.

The science of evolution

The scientific theory of evolution is an attempt to explain the natural causes of the development of life (including humans). Notice that having a scientific explanation for some phenomenon does not mean God had nothing to do with it. For example, knowing the biology about where children come from does not alter our belief that children are a gift from God, that God knit them together in their mothers’ wombs. So too, the fact that we’ve discovered natural causes for the development of life does not mean God had nothing to do with it.

What is this scientific explanation? The big picture of evolution is that all life forms on earth have common ancestry. That does not mean current species evolved from each other: whales did not evolve from hippos, nor did humans evolve from chimpanzees. Rather, common ancestry claims that for any two organisms, if you go back far enough in their family trees, you’ll come to a population of organisms from which they both descend. For whales and hippos, that looks to be about 55 million years ago; for humans and chimps, it is 6 or 7 million years ago.

So how does it work? Zooming in a bit on the picture of evolution, there are two key components to the explanation: variation and selection. That is to say, offspring differ slightly from their parents (variation), and only some of those offspring go on to have offspring of their own (selection). There is vast agreement today on this much of the picture among professional scientists in the fields of biology and medicine (99% of them agree),¹ and the evidence for it today from genetics alone is overwhelming.² This basic picture is corroborated through the fossil record (yes, there are now lots of transitional fossils), comparative morphology (the shape of organisms), and biogeography (the distribution of species around the world).

The disagreements among professionals come when we zoom in even further to ask how the variation and selection take place. There is a popular or lay-level understanding of evolution according to which random genetic mutations are the only source of variation, but all evolutionary biologists today recognize there are several mechanisms for variation and argue over the relative importance of these. There are similar kinds of arguments over selection, but again, common ancestry is a settled issue among professionals in the field.

Evolution and the Bible

So, what do we Christians do with this? Some believe the scientific picture contradicts what is in Scripture, and since God is responsible for Scripture in some sense (God inspired it), it is difficult to believe that God would allow things to get into the Bible that aren’t true. Okay, but don’t we also believe God is responsible for the natural world (God created it)? And it is equally difficult to say God would have put things there that aren’t true. There must be a way, then, to reconcile the truths in Scripture with the truths in the natural world.

First, remember that although God is the “author” of both Scripture and the natural world, we finite and fallible humans are the ones interpreting these “books”. And throughout history, there are clear examples of us getting things wrong: geocentrism (the theory that the earth is stationary and in the center of the universe) is an easy example of our error we’ve made in the past in both biblical interpretation and science.

Next, just like in evolution, the further we “zoom in” on the specifics of our interpretations of Scripture, there is less consensus. Yes, all humans sin and Jesus must save us. But does Scripture demand that Adam and Eve were the only two humans initially created? Genesis 1 suggests maybe not, as does Cain’s fear about being sent away. And yes, God providentially guides the world and guarantees the final outcome. But does God dictate all the details of how things develop, or is there room for some contingency among an evolving creation?

These (and many more) can be tricky questions, and we would be wise to discuss them openly and graciously with each other. I’m convinced the essentials of Christian doctrine are not called into question by evolution, and there is enough flexibility among less central doctrines to find ways of harmonizing them with the truths of science.