The study of the Holy Spirit (sometimes called pneumatology) is an under-developed area of Christian theology. While volumes of ink have been dedicated to explicating the precise relationship between the Father and the Son, the third Person of the Trinity remains much more elusive, sometimes showing up only as a kind of afterthought. This is not to say, of course, that matters of pneumatology remain entirely unaddressed. For example, the Holy Spirit is often discussed in terms of the relationship of the Father and the Son, as that which binds them together—and also binds us into the trinitarian life which they share. Some theologians grappling with questions of pluralism talk about Christ and the Holy Ghost as a way to balance particularity and universality, as Christ comes in a particular time and place, where the Holy Ghost is sent throughout the world. One twentieth century theologian (Wolfhart Pannenberg) even attempts to bring the Holy Ghost into the dialogue between science and religion, and proposes that it might be understood as a kind of cosmic force field. But compared to many other areas of theology, there isn’t all that much work on the subject.
Mormonism similarly exhibits theological gaps when it comes to the third member of the Godhead. An LDS framework, of course, brings some unique questions to any discussion of pneumatology. Latter-day Saints conceptualize the Holy Ghost as an individual center of consciousness, a distinct person. The classic matters for speculation in an LDS context therefore include such conundrums as, Who is this mysterious person? Where did he come from? Are we even absolutely sure that he is male? Will he ever get a body? But rather than tackle these questions, I would like to ask something somewhat more basic: in the context of the LDS understanding of God, why is the Holy Ghost necessary? What unique function does he serve?
The primary role played by the Holy Ghost seems to be a communicative one. He bears witness of truth, inspires us to do good, brings answers to prayers, and so forth. But this raises the question of why the Father can’t talk to us directly. This is not, after all, a God who is Wholly Other, for whom communication with mortal, finite beings might pose a dilemma; LDS theology posits him as an exalted being not entirely unlike us. Why, then, does he need a intermediary to facilitate conversations with his children? The Holy Ghost is also traditionally understood as playing a role in sanctification. But again, assuming that that this is accomplished through the power of the atonement, it does not seem entirely clear what unique and necessary role the Holy Ghost plays in this process.
Perhaps the most intriguing comment about the Holy Ghost in LDS scripture is found in D&C 130:22, which establishes that the Holy Ghost is a “personage of Spirit,” and goes on to make the observation, “were it not so, the Holy Ghost could not dwell in us.” This hints that there are limits to what a corporeal God can do. Might the doctrine of a spirit-body-only Holy Ghost be a way of maintaining something like the traditional notion of divine omnipresence (God is everywhere), while holding on to the idea that the Father has body of flesh and bones and thus presumably exists at one particular location in space? Though given that the Holy Ghost is understood as a personage rather than an impersonal, diffuse force of some kind, maybe not. What are the advantages, exactly, of not having a physical body? And if there are abilities which spiritual beings possess that exalted ones do not, what are the implications for our notion of exaltation?