Taken as a whole, Reflections of a Political Economist is a fine collection of essays. But if you want to get an idea of the esteem William “Bill” Niskanen was held in at the Cato Institute, go ahead and skip to the end, chapter 41, “A Personal Reflection on the Trinity.” There is nothing political in this chapter. It is a sermon that Niskanen, who died last week of a stroke at 78, delivered at his Christ Church in Washington D.C. on Trinity Sunday, 2006.

Niskanen’s book was published by Cato, which has a reputation as a very secular institution. I worked there and can say from experience that the reputation is both deserved and overstated. Cato is nervous about religion, true. However, it is OK with the use of some religious texts to help support its vision of libertarianism in politics.

Cato vice president David Boaz, following in the footsteps of Thomas Paine, opened The Libertarian Reader with a passage from the first book of Samuel, chapter 8 — the bit where the prophet warns the people of Israel about the catastrophically high price they will pay if they insist on a having a king. (“He will take your sons, for his chariots. And he will take your daughters, to be cooks. And he will take your fields…”) Boaz elsewhere included the same passage as part of “the prehistory of libertarianism.”

So there was some precedent for Catoistas pointing out that religion-inspired liberty and the more secular varieties can play nice. But to publish a sermon on a specific aspect of theology, and one unique to Christianity and not even accessible to natural theology? The only person in the building who could pull that one off was Bill Niskanen.

He was chairman of Cato from 1985 to 2008 and chairman emeritus thereafter. Yet it wasn’t just his title that compelled publication. The New York Times obit that ran over the weekend called Niskanen a “blunt libertarian economist,” and that’s one way of putting it. He was  a University of Chicago-trained economist who was run out of jobs at Ford Motor Company and then the Reagan administration for speaking his mind.

Niskanen opposed Ford’s push for protection against Japanese auto imports and he opposed aspects of what became President Reagan’s 1986 tax reforms. He also drew sharp attacks from Walter Mondale for arguing the blindingly obvious: one big reason for the sex disparity in pay is that women leave the workforce to raise children. The Reagan White House insisted that Niskanen was speaking only for himself. In his memoirs, Niskanen called White House chief of staff Donald Regan “a tower of jelly.”

Now, pretend for a minute that you are head of publications at the Cato Institute. Bill Niskanen comes to you with a collection of essays on just wars, tax burdens, global warming treaties, defense dollars, corporate scandals, and the like, and this very earnest man has included as a coda his sermon on the Father, Son, and Holy Ghost. You want to tell him to take it out?

I’m glad that didn’t happen because it’s an interesting little sermon on the Trinity and it reveals a side of Niskanen most of us never got to know. He delivered it at his longtime church. Christ Church is an Episcopal church, but we learn that’s not where he started. “As a former Baptist,” he says, getting into the meat of the message, “I am first inclined to look to the authority of the Scriptures.”

And there the problems begin. The word Trinity appears nowhere in the Bible and is most evident in a verse in the first letter of John that most scholars believe to be a much later addition to the text. Rather, the Trinity was a way of resolving several problems about Jesus and about a figure that Jesus spoke often of, the Holy Spirit.

“The Roman church,” Niskanen preaches, “claimed that they had resolved these differences by going beyond any of these positions asserting that Jesus was both divine and human, as he always was and always will be. This then left the awkward problem of the nature of the Spirit, to which there are numerous references in the Scriptures. So the Roman church also escalated the spirit to a co-equal and co-eternal status with the Father and the Son. And, voila, the doctrine of the trinity was born — later to be affirmed by two major fourth-century church councils.”

That is the description of Bill Niskanen, political economist, and it sounds too cynical to Niskanen, lay theologian. You can already hear him dialing it back when he invokes the church councils, and he next raises the “role of reason, the third source of Christian authority, in understanding the doctrine of the trinity.” He says that “for the most part” the Trinity lies “beyond reason” and confesses this leaves him “very uneasy.”

Niskanen explains himself: “I am not averse to living with mystery; all sorts of conditions that I value are a mystery to me. But it does lead me to question whether there is some perspective on the trinity that is both better rooted in the Scriptures and more coherent.” And he proceeds to offer just such a perspective.

I’ll let readers peruse his solution on their own and close instead with Niskanen’s whimsical words on the Holy Spirit. “On occasion,” he confesses, the Spirit’s “still small voice speaks to me so clearly that I am surprised that others in my presence do not also hear it. Like right now when it tells me that ‘Time’s up. Episcopalians prefer short sermons.'”