The major focus of Long’s work is the dialogue between philosophy and theology and he is often characterized both as a philosophical theologian and philosopher of religion. Attracted in his early days to the work of Hegel and British and American Idealism, he is influenced in particular by the work of Karl Jaspers, Martin Heidegger, Paul Tillich and John Macquarrie. Appealing to the theories of experience in the tradition of so-called radical empiricism, Long argues for transcendent dimensions of general human experience to bridge the gap between specifically religious and ordinary experience. 