In Characters In Search of Their Author, the Gifford Lectures delivered at the University of Glasgow in 1999-2000, Ralph McInerny discusses natural theology as it can be discussed in the present philosophical climate. The first five lectures ask Whatever Happened to Natural Theology? , and trace the fate of philosophical efforts to establish the existence and nature of God in modern times. In the second set of lectures, dealing with The Recovery of Natural Theology, McInerny defends the viability of the philosophical effort against certain dominant trends in contemporary philosophy.

It has been the practise of Gifford Lecturers to write a book based on the lectures, often years after the event. This book contains the text of the lectures McInerny actually delivered.