Three features of moral apologetics are particularly powerful means, individually and collectively, to make the case for God’s existence. The first is its cumulative potential. Cumulative case arguments in apologetics typically conjoin arguments like the teleological, cosmological, and historical arguments—or some such combination. Such cumulative cases are great, but here I mean a cumulative moral argument in and of itself. The most common sort of moral argument puts the focus on moral facts like moral values and duties, and perhaps under the penumbra of such concepts fall a constellation and cluster of other important moral dimensions in need of explanation like rights, agency, ascriptions of responsibility, human dignity, an human equality; but in addition to such facts, think also about something like moral knowledge. This expands the focus from metaphysics and ontology to moral epistemology, and thinkers like Mark Linville, Angus Ritchie, J. P. Moreland, and R. Scott Smith have done an admirable job fleshing out this aspect of moral apologetics.

What Kant referred to as “moral faith” broached two other features of morality: whether achieving the life of virtue is possible, and whether, even if it is, it’s consistent with happiness. John Hare puts a great deal of emphasis on these aspects of moral apologetics. The Moral Gap, for example, discusses both; the notion of the “gap” that God enables us to cross is all about our need for moral transformation and, especially, God’s grace and assistance to meet the moral demand, something we can’t do otherwise. The second part of moral faith, pertaining to the ultimate correspondence of happiness and virtue, has to do with nothing less than the ability to believe the moral life is a fully rational enterprise—a solution to what Sidgwick called the dualism of the practical reason. Classical Christian theism impeccably and best sustains both of these aspects of Kantian moral faith, and thus these additional aspects of morality allow for two additional variants of moral apologetics. Put all four parts together—moral facts, moral knowledge, moral transformation, and moral rationality—and the result is a powerful cumulative moral argument for God’s existence.

In addition to being a cumulative case, it’s arguably preferable for numerous reasons to advance an abductive moral argument. An abductive case is an inference to the best explanation. This form of argument need not deny that other alternative explanations of the range of moral facts (just discussed) are entirely deficient with nothing to add to the discussion. Numerous among them may well be able to do some measure of explanatory work. Consider the world in which we live. Especially if theists are right that this is a rich, fertile world imbued with all sorts of value and significance, and populated by creatures made in God’s image and invested with a range of powerful epistemic faculties, theism would predict that the resources of this world will provide powerful insights into its ubiquitous moral features. It would be altogether surprising if it were otherwise. The reason that morality provides evidence for God is not that the world alone can explain nothing about morality, but rather that the world and theism together can provide the considerably better explanation of those realities. An abductive case builds on the common ground shared by believers and unbelievers alike and invites a conversation about what can better explain the full range of moral facts and can explain them robustly, without domesticating them, watering them down, or subtly changing the subject.

My preferred approach to moral apologetics also features a strong recurring theme of teleology. If theism is true, and we have been created for a reason and purpose, we have been imbued and invested with a telos: a goal or aim. This makes excellent sense of the ontology of both goodness and oughtness. God as the ultimate Good, and the one in whose image we have been created, is both the source and goal of our lives and, ultimately, of any goods we enjoy.

Teleology also facilitates the acquisition of moral knowledge. So long as the operative meta-narrative of the human condition is that we’re pushed and pulled around by the ineluctable forces of the material world, we are hard pressed to maintain confidence in our belief-formation processes to reliably track the truth, moral or otherwise. But if God designed us in such a way that our cognitive apparatus puts us in touch with reality and makes real knowledge possible, then we can take the deliverances of our deliberations and reflective processes veridically.

Teleology functions at the foundation of Kantian moral faith as well, bolstering the two variants of moral apologetics resting on its foundation. If God created us for fellowship with him—to love God with all of our hearts and souls and mind and strength, and our neighbor as ourselves—we simply have far better reason to think that total moral transformation is possible. If this world is all there is, and the resources of naturalism exhaust the tools at our disposal, morality seems to stir a desire within us that can’t be satisfied, a thirst that can never be quenched. For this life and world will end without anyone ever having achieved a state of moral perfection. But if Christianity is true, then our desire to be delivered entirely from every last vestige of sinfulness and selfishness is no futile pipe dream, but an intimation of things to come, an echo of eternity, when all is set right, all tears are wiped away, and we will be changed entirely to conform with the One who made it possible. And in that state, if Christianity is true, we will find our deepest joy—when holiness and happiness not merely conjoin or cohere, but kiss and consummate. This was God’s intention and our God-invested telos all along.

So, construct a powerful, patient abductive moral apologetic, wrapped with a robust teleology that encompasses every part of the cumulative case for God’s existence, and you’ve got the makings for a formidable argument indeed—one that can illumine the mind, stir the heart, and move the will.

Photo: "Construction" by A. Levers. CC License.