“Hear, Israel, the Lord is our God, the Lord is One” (Dt 6:4). The confession of the one God is the great gift of Israel to the world—a gift not of philosophical speculation but of divine revelation. Shema Yisrael Adonai eloheinu Adonai ehad!
The confession of the oneness of God moved beyond the national boundaries of Israel into the Gentile world through the proclamation of Jesus Christ. Jesus quotes the Shema in answer to the question “Which commandment is the most important of all?” (Mk 12:28-29), and the Apostle Paul reiterates the confession in his epistles: “Therefore, as to the eating of food offered to idols, we know that ‘an idol has no real existence,’ and that ‘there is no God but one.’ For although there may be so-called gods in heaven or on earth—as indeed there are many ‘gods’ and many ‘lords’—yet for us there is one God, the Father, from whom are all things and for whom we exist, and one Lord, Jesus Christ” (1 Cor 8:4-6). In the early 2nd century the Shepherd of Hermas announced the mandate of the monotheistic confession: “First of all, believe that God is One, even He who created all things and set them in order, and brought all things from non-existence into being, Who comprehendeth all things, being alone incomprehensible” (mand.1.1). The ecumenical creed of Nicaea begins: “We believe in one God, the Father Almighty, Maker of all things visible and invisible.”
Yet more than a few have wondered whether the patristic Church, with its developed doctrine of the Holy Trinity, gravely compromises the monotheistic confession. How can Christians possibly think that asserting three divine persons does not deny the unity of the Godhead? As the pagan philosopher Celsus wrote in the 2nd century: “If these men worshiped no other God but one, perhaps they would have a valid argument against the others. But in fact they worship to an extravagant degree this man who appeared recently, and yet think it is not inconsistent with monotheism if they worship His servant” (quoted in Origen, Cels. 8.12). For Celsus Christians are confused and illogical—they profess belief in one god but they clearly worship at least two divine beings. As a happy polytheist Celsus is not critical of those who worship many gods; he dismisses Christians, rather, for their obtuseness. If Christians are going to claim to be monotheists, then they should at least be consistent monotheists!
For the critics of trinitarianism, whether they be Jewish, Muslim, or pagan, the assertion of divine oneness is clear and unmysterious. This is most certainly the case at the level of polemic: if God is one numerical self, then polytheism is false; if God is one numerical self, then he alone is worthy of worship and absolute obedience; if God is one numerical self, then Christians are in fact functioning polytheists. As Rabbi Abbahu declared in the late third century, commenting on Isaiah 44:6: “‘I am the first,’ for I have no father; ‘and I am the last,’ for I have no son, ‘and beside Me there is no God,’ for I have no brother” (Ex. R. 29:5). The Quran is equally clear: “In the Name of God, the Merciful, the Compassionate. Say: ‘He is God, One, God, the Everlasting Refuge, who has not begotten,and has not been begotten,and no one is equal to Him” (Surah 112). Yet Christian theologians continued to insist that their Holy Trinity is perfectly compatible with the monotheistic confession: see Robert Wilken, “Not a Solitary God: The Triune God of the Bible.”
In this article, though, I am not concerned to defend the trinitarian doctrine. I want, rather, to suggest that the confession of the one God is more mysterious and enigmatic than we know. Once the Church comes to understand that God has created the universe from “out of nothing,” then the monotheistic confession must itself be apophatically re-interpreted. If God radically transcends the created order—if he is God and not a god—then how can we count even up to one? In the words of St Thomas Aquinas: “There is no number in God.”
Denys Turner invites us to engage in a thought experiment. We bring together all the scientists in the world, and we ask them to make an exhaustive list of everything that exists. The list will no doubt number in the billions, trillions, zillions. After the list is finished, would it then be legitimate for someone to say, “But you have omitted God. Don’t forget to add him to the list”? No, Turner replies. “God cannot be counted in any list of the ‘everything that is.’ God’s oneness is not the oneness of mathematics, as it would be were I to say of any creaturely oneness: ‘I’ll have one pie for lunch, not two'” (Thomas Aquinas: A Portrait, p. 120).
The confession of the one God immediately brings us into the transcendent mystery of the God who is not a god. The ontological cleavage between creator and creation is decisive. We can number the gods, for the gods (if they exist) belong to the world of nature. But the one God plus the world does not equal two. As (Pseudo-)Dionysius writes, “There is no kind of thing that God is” (quoted in Turner, p. 120). St Gregory Palamas is even more provocative: “Every created nature is far removed from and completely foreign to the divine nature. For if God is nature, other things are not nature; but if every other thing is nature, He is not a nature, just as He is not a being if all other things are beings. And if He is a being, then other things are not beings” (Capita 78).
The confession of the one God is not more comprehensible than the Christian confession of the trinitarian persons. Its ineffability is not “somehow less intense than that of the divine Trinity,” comments Turner:
Christian Trinitarianism does not rock a unitarian boat that would otherwise be plain sailing for Jews and Muslims. … Whether by God’s oneness or God’s threeness, we are in equal measures theologically benighted, or, as one might more positively put it, believers of all three faith traditions are thereby invited into a participation in love with the same unknowable, indescribable Godhead. (pp. 130-131)
God is One … gloriously, ineffably, wonderfully One … but not by counting.