By John M. Grondelski

But first a note from Robert Royal: Probably the deepest challenge of our time, as our columnist demonstrates today, is the defense of the human person, as we've always understood persons in the Christian tradition. AI is the most evident coming challenge (next week we'll bring you commentary on Pope Leo's first encyclical that's on this whole subject).

But there are also many deeper questions that have long troubled our times - we can't even say who is a man or a woman. At TCT, we're committed to battling for truth despite the immediate challenges like AI as well as the long-term cultural trends. If you understand what's at stake - and I'm sure you do - please, join us in this work. The harvest could be great but the laborers fewer than we need. Help us make the Catholic case even stronger. Support TCT today.

Now for today's column...

Modern philosophy flatters itself by claiming it was responsible for the "turn to the subject," i.e., the human (and, usually, a very subjective understanding of the human). But focus on the human is hardly a modern discovery.

St. Irenaeus, a second-century bishop-theologian, is noted for his line gloria Dei vivens homo – "the glory of God is man fully alive." Nor did the bishop of Lyons pluck that thread out of nowhere: the Psalmist praises the Creator for making man "a little less than the angels." (Psalm 8:5) Eastern Christianity long recognized that God's work of salvation was really deification: of bringing the full image and likeness of God in man to flower. (Genesis 1:27)

The dignity of the human person was so central to the pontificate of Pope St. John Paul II that it was the focus of his inaugural encyclical, "The Redeemer of Man" (Redemptor hominis). Nor did that pope tire of quoting Gaudium et spes (no. 22) that Jesus Christ "fully reveals man to himself." Note what the Council says – and doesn't. The Council doesn't say Christ "fully reveals God to man" (though that's true). It affirms Jesus "fully reveals man to himself."

Carl Trueman brings those insights in his new book, The Desecration of Man: How the Rejection of God Degrades Our Humanity. He argues that, in some ways, Nietzsche was ahead of his time. Proclaiming the "death of God" to a world still coasting on religious gases was ineffective. As with nominalism, the culture still concealed the gaping abyss the "death of God" entails – not least of which is destroying the divine image and likeness in man.

In three chapters, Trueman goes on to demonstrate how contemporary man is achieving that in the area of sex (the sexual revolution and abortion), artificial reproduction (IVF and surrogacy), and death (an enemy which, if it can't be stopped, can at least be forced to bend to one's wishes about when and where).

Man as the divine image and likeness is the unifying theme in Trueman's work: if the human person is made in the image of God who is good, then man's forays into sin constitute a defacement of that image.

That too is not necessarily a new insight: already in the fifth century, Pope Leo the Great, in his first sermon for Christmas, admonished Christians to "remember your dignity" (albeit as redeemed by grace through the Incarnation). But Trueman argues persuasively that moderns are not simply disfiguring their divine image and likeness. Rather, they are actively and almost with pleasure working to "desecrate" that image, to try to destroy the divine image in man by replacing it by an autonomous human god.

This isn't just a moral question: what sins people commit. It's an anthropological question, the one the Psalmist posed: "Who is man?"

Trueman's starting point is important for two reasons.

First, it provides a common ecumenical and interreligious point of departure. Jews and Christians can share a mutual perspective while, Scripturally based, it may ameliorate some of the notions of radical human corruption that reigned among the classical Reformers.

Second, it applies to all men: all human perso...