Tritheism

I and the Father are one.

— John 10:30

Tritheism is a heretical account of the Trinity that multiplies the one divine essence shared by the Father, Son, and Holy Spirit into three complete and numerically distinct divine essences, one belonging to each person.¹ Where the historic doctrine of the Trinity confesses one essence held whole and undivided by three persons, tritheism turns the three persons themselves into three separate gods.² It stands opposite modalism, which denies any real distinction of persons, and opposite subordinationism, which denies the Son and Spirit’s equal deity; tritheism instead protects the distinction of persons only by dividing the very essence they share.

Historical Origin

Van Mastricht identifies tritheism’s founder as John Philoponus (c. 490-c. 570), an Alexandrian philosopher and grammarian also called John the Grammarian, who threw his support behind monophysite Christology around the time of the Fifth Council of Constantinople (AD 553).¹ Philoponus argued, in his treatise Arbiter, that “hypostasis” is best understood in the Aristotelian sense of a primary substance and “ousia” as a secondary substance or universal nature, a framework that, applied to the Trinity’s three hypostases, yielded three primary substances rather than one shared universal nature.¹ Mastricht dates the resulting movement’s rise to around AD 574, under an emperor he names as Phocas, though the work’s modern editors note that Phocas did not in fact reign until AD 602-610 and that the Eastern Roman emperor of AD 574 was Justin II.¹ Elsewhere in the same work, Mastricht places the Tritheists more loosely “at the beginning of the seventh century.”²

Mastricht reports that the Tritheists arose “in order more strongly to oppose the Sabellians,” the modalists who denied any real distinction of persons, and that they “categorically professed that there were three gods.”¹ He locates two related but distinct errors nearby in time. A fourth-century sect he calls the Triformians, active from around AD 370, held that the one God “had parts that made up the Trinity, as if God were completed from these three parts,” with the result “that God was not perfect in himself, nor was the Father, or the Son, or the Holy Spirit.”¹ And a group he calls the Tetratheists, active before Emperor Anastasius (before AD 485) and later known as Theodosians, Damianists, or Angelites, “taught that besides the three divine hypostases there existed a certain fourth essence which was common to the three and communicated itself to them, on account of which communication they became gods.”¹ Sixteenth-century Switzerland saw a further variant in Valentine Gentile, who held three eternal but subordinate divine essences, “speaking in barbarisms,” in Mastricht’s phrase, when he “called the essence of the Father essencing and the essences of the Son and the Holy Spirit essenced.”¹

Core Tenets

Mastricht summarizes the Tritheists’ central claim: they “stated that there were three complete divine essences, belonging respectively to each divine person,” in place of one essence common to all three.¹ His chapter on the Trinity restates the same point: the Tritheists, “according to the number of the three persons,” numbered “also… three essences,” wanting the persons “to differ as so many deities, and thus from this arise three gods.”²

Mastricht diagnoses the error’s root cause as a failure of theological distinction: the Tritheists, he writes, “could not distinguish carefully enough between essence and person.”¹ Where the historic doctrine holds that one essence is common to three really distinct persons, tritheism collapses that distinction by treating each person as though it possessed an essence of its own.

Confessional and Biblical Response

The Second London Baptist Confession states the doctrine tritheism denies: “In this divine and infinite Being there are three subsistences, the Father, the Word or Son, and Holy Spirit, of one substance, power, and eternity, each having the whole divine essence, yet the essence undivided.”³ Each person is not a third of the essence, nor an essence of his own; each has “the whole divine essence,” one essence held in common rather than divided or multiplied.

Barrett grounds this confession in the doctrine of divine simplicity: because God is not composed of parts, “the one essence is not split into three things (i.e., tritheism) but wholly and personally subsists in three distinguishable yet inseparable persons.”⁴ The persons are distinguished only by their eternal relations of origin, the Father’s begetting the Son and the Spirit’s proceeding from Father and Son, not by each possessing a nature of his own.⁴

Scripture states the same unity the confession and Barrett describe. Israel’s own confession admits no division in God: “Hear, O Israel: The LORD our God, the LORD is one” (Deut. 6:4). Jesus applies that same oneness to himself and the Father directly: “I and the Father are one” (John 10:30). Paul states the apostolic confession in explicitly monotheistic terms even while naming Father and Son together: “for us there is one God, the Father… and one Lord, Jesus Christ” (1 Cor. 8:6). None of these texts divides the divine essence into separate gods; all confess one God who is Father, Son, and Holy Spirit.

Modern Forms

Bavinck warns that a similar error threatens whenever the Trinity’s three persons are pressed too literally into modern categories of individual personhood. Applying “personality” language to the Trinity strictly, in the sense that “modern people speak of ‘selves,’” would, he says, “make us guilty of the heresy of tritheism.”⁵

Bavinck’s warning corresponds to a live debate among contemporary defenders of “social trinitarianism,” a family of models associated with Cornelius Plantinga Jr., William Hasker, and Leonard Hodgson, among others, that explains the Trinity’s unity chiefly through the persons’ relationships rather than through one shared numerical essence.⁶ Critics have pressed the charge Bavinck anticipates: William J. Hill argues that Hasker’s account, in which the divine nature is only “generic in kind” rather than “identified in a real and ontic way” with each person, cannot avoid “the implication of tritheism.”⁶ Plantinga himself is aware of the charge and argues that his own model escapes it, though his case turns on redefining what counts as monotheism rather than on the one-numerical-essence formulation the Reformed confessions state.⁶

Related Doctrines

References

Petrus van Mastricht, Theoretical-Practical Theology, vol. 2, Faith in the Triune God, ed. Joel R. Beeke, trans. Todd M. Rester (Grand Rapids: Reformation Heritage Books, 2019), chap. 8, “The Unity of God,” 206-221. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰
Van Mastricht, Theoretical-Practical Theology, vol. 2, chap. 24, “The Most Holy Trinity,” 538-567. ↩ ↩² ↩³
The Second London Baptist Confession of Faith (1689), chap. 2, “Of God, and of the Holy Trinity,” para. 3. ↩
Matthew Barrett, None Greater: The Undomesticated Attributes of God (Grand Rapids: Baker Books, 2019), chap. 5, “Is God Made Up of Parts? Simplicity.” ↩ ↩²
Herman Bavinck, Reformed Dogmatics: Abridged in One Volume, ed. John Bolt (Grand Rapids: Baker Academic, 2011), chap. 7, “Knowing God.” ↩
Keith Wesley Goad, “Plantinga’s Simplicity, Being, and Person: A Discrepancy in Definition,” in “Trinitarian Grammars: A Comparison of Gregory of Nazianzus and Some Contemporary Models” (PhD diss., The Southern Baptist Theological Seminary, 2010), 230-262. ↩ ↩² ↩³