The opening verse to Psalm 19 is famous for its celebration of God's majestic creation: "The heavens declare the glory of God. The skies proclaim the work of His hands." Yet the psalm is memorable too for showing a striking feature of biblical Wisdom literature: after spending the first six verses praising the natural world, it abruptly changes gear to commend the beauty of God's moral order: "The law of the Lord is perfect, refreshing the soul."

While seeming strange to modern ears, the sudden transition sits comfortably with the overall plotline of the Bible. Since both the natural world we perceive with our senses and the unseen moral realm we know though our conscience are alike created and sustained by God, the authors of Scripture frequently shift from one domain to the other.

A related truth learned from Scripture is that both realms bear the brunt of humanity's rebellion against its Creator; not only does the physical creation groan under sin's weight, but disunion with God breeds chaos in the moral realm. This disorder is evident in Genesis 4, where, after murdering his brother, Cain's shabby evasiveness identifies him as the first Nihilist — the first to consciously deny any moral obligation toward others. When God confronts Cain over Abel's absence, the whining response seems straight from the textbook of modern nihilism: "Am I my brother's keeper?"

While the selfishness that defines nihilism is ingrained within our fallen natures, few will publicly admit to owning this worldview. Hence secularists often insist that the Christian God can be rejected without collapsing moral obligations or plunging necessarily into nihilism. "We can be good without God" is a commonly voiced viewpoint, but this claim invites a sceptical response. If the existence of a transcendent moral realm is denied on the grounds that it cannot be demonstrated using the tools known to physical scientists — and devoted materialists typically make such claims — then on what grounds are genuine ethical values conceivable?

Rather than tracing moral values to a transcendent realm created by God, most secularists assume that they originate in the "neural circuitry" within human brains. On this view, the billions of interconnected nerve cells within the brain evolved to manufacture ethical judgments in much the same way that the pancreas acquired the ability to produce insulin, the liver to make glucose, or the kidneys to secrete vitamin D. As hominid brains developed these capabilities, their evolving mental capacities ostensibly fostered the emergence of altruism, thus enabling group living and the emergence of humane societies.

Such explanations are widely taught to students, but there is a worrying problem with the materialist stance.

After all, in a world without transcendent immaterial entities, it's unclear how ethical values invented by an individual human brain have any application on a wider or universal scale. If, as materialism insists, humans are simply walking test tubes comprising trillions of molecules fizzing away in vastly complex chemical reactions, why should the contents of one test tube feel obliged toward those of another? Neurobiological thinking might explain your preference for chocolate milkshakes and my fondness for vanilla, but it struggles to account for universal moral values that make civility and decency possible.

Dogmatic materialism of what Professor Donald MacKay used to call the "nothing buttery variety" — the view that humans are nothing but atoms and molecules inevitably leads humanity into a moral wasteland. Lacking grounds for ethical responsibility or a basis for the broad applicability of moral values, the materialist philosophy can only breed nihilism, not cure it. As Dan de Witt put it in his fine little book, Jesus or Nothing, only Christ can do the latter:

The gospel gives an explanation for our existence, clarity for our confusion, grace for our guilt, meaning for our mortality, and answers for our adversaries.