Today, many Reformed theologians are advocates of “classical theism.” A few hints from Richard Muller’s volume on the Trinity raise the question of whether the Reformed tradition fits neatly into what passes as classical theism today. A few brief gleanings will suffice to raise the issue.
Classical theists insist above all on the unity of will in the Trinity. It is argued that will is an attribute of nature, not person, and so any plurality of wills in God implies a plurality of natures. It’s Arian at best, tritheistic at worst.
Reformed treatments of the pactum salutis – the covenant between Father and Son by which the Son is designated as mediator and surety – don’t remain within this one-will paradigm.
Polanus writes: “The Son . . . in incarnate because he wills voluntarily to be made our sponsor, voluntarily subjecting himself to the Father not according to nature, but according to the voluntary arrangement (oeconomia) or dispensation: a natural subjection is, surely, distinct from an economic or dispensatory subjection: he is made freely obedient to the Father, not according to divine nature in itself . . . , but according to will: obedience, indeed, is not the natural act of a nature (actus naturalis naturae). but of the will or free accord of the person of Christ (voluntarius personae Christi)” (Muller, 267).
Polanus explicitly links will to person instead of nature – at least, a will to obey is exercised at the level of person, rather than nature. And the mere fact that the Son would will to be sponsor indicates that the Son doesn’t will identically to the Father and Spirit (since neither Father nor Spirit Himself wills to be sponsor).
Another key feature of classical theism is its minimalist conception of divine “Personhood.” It excludes elements of “personality,” and simply means (in a Boethian turn) an individual subsistence of a rational nature. When defining persona, Reformed theologians stuck with Boethius or something like him (Muller, 177-82) but things are different when they prove the distinct personhood of the Spirit.
Though the Reformed recognized that many of the images of the Spirit in Scripture suggest an impersonal force, they argued that the Spirit was in fact a person. Then the aim is not merely to demonstrate that the Spirit has a distinct subsistence, but that the Spirit’s actions are the actions of a being endowed with something close to what we call “personality.”
Muller (347) summarizes: “It is abundantly clear, the orthodox insist, that the divine names and attributes given to the Spirit, the distinction made between him and the Father and the Son, and the various theophanies or ‘personal actions’ and operations of the Spirit . . . evidence a personal sense of the word ‘spirit.'”
Muller cites passages that speak of the Spirit being “grieved,” anointing Christ, leading Israel through the wilderness. The Spirit comforts, teaches, testifies, prophesies, guides believers into truth, intercedes, is tested by those who lie to him (Muller, 349). The Spirit is sent into our hearts to cry out Abba, Father. Muller explains that for the Reformed “this is not personification, but a direct reference to an operation of the Spirit,” an operation that enables the believer to cry to the Father (Muller, 347).
These have remained standard arguments for the personality of the Spirit into the twentieth century (Berkhof employs them, for instance). And they assume that a divine Person is one who speak, teaches, interacts with other divines Persons and with human beings. The arguments assume that divine Persons have something analogous to human “personality.”
These are, as noted, merely hints. And perhaps the conclusion is: So much the worse for Reformed orthodoxy. At least, they should give pause to Reformed theologians who want to use “classical theism” as a standard of Reformed orthodoxy.
But this, in turn, raises the question of whether “classical theism” is as opposed to the notion of divine “personality” as classical theists suggest. Michel Barnes – no social Trinitarian he – has noted that for Gregory of Nyssa, a hypostasis is “an existent with a real and separate existent.” But he also says that Gregory has “a psychology of the Individuals of the Trinity” (quoted in McCall, Which Trinity? Whose Monotheism?, 239).
McCall summarizes Barnes’s point with regard to the Spirit: “‘what is at stake is not simply the ‘separate reality’ of the Holy Spirit, but the Spirit’s status as what we would call a ‘person’: the Holy Spirit acts and says such and such things, and defines and is grieved and is angered.’ Barnes thus concludes that ‘there is reason to believe that [Gregory] understood the need for stronger and clearer language on both the distinct and personal reality of the Holy Spirit – language which made clear that the Spirit like the Son was a psychological entity with a distinct existence.’ Barnes concludes thus for good reason; as Gregory himself says, the Holy Spirit ‘exists as a person, able to will, self-moved . . . for its every purpose having its power concurrent with its will'” (239).
For Gregory as for the Reformed scholastics: If you want to suss out the meaning of “person,” follow the pneumatology.