The chisel marks on this monument to human imagination continue. Justin introduced the multi-personal God of Numenius into Christianity. One generation later, Tertullian (~155–220 AD) coined the formula—una substantia, tres personae—one substance, three persons—that became the backbone of Trinitarian confession.

Before examining what Tertullian introduced, let’s ground our examination in what is commanded in the Scriptures:

Deuteronomy 6:14: “You shall not go after other gods, of the gods of the peoples who are around you.”

Exodus 23:32–33: “You shall make no covenant with them, nor with their gods…if you serve their gods, it will surely be a snare to you.”

Deuteronomy 12:30: “Be careful that you are not ensnared to follow them after they are destroyed from before you, and that you not inquire after their gods, saying, ‘How do these nations serve their gods? I will do likewise.’”

Daniel 9:5: “We have sinned… and have rebelled, even turning aside from your commandments.”

Nehemiah 9:26: “They were disobedient, and rebelled against you, and cast your law behind their back.”

God could not have been clearer that following the gods of the heathen would be a snare to His people. He made no provision for making common ground with other gods or the practices offered in service to them. God calls it ‘speaking rebellion.’ In the Old Testament, it came with a death sentence.

Now, let’s take note of what Tertullian himself confessed about his source.

Confession One: He Got It From a Gnostic

“I am introducing…one thing out of another, as Valentinus does…wherein we declare that the Son is a prolation from the Father…just as the root puts forth the tree, and the fountain the river, and the sun the ray. For these are…emanations, of the substances from which they proceed.” —Tertullian, Against Praxeas, 8.

He did not commend his audience to Scripture. He did not claim he was repeating what the apostles had taught. He did not appeal to the Jews. That silence is deafening. He got it from Valentinus the Gnostic. Tertullian said so himself.

Tertullian displayed his knowledge of the Valentinian system in contending against it:

“Although they would have him be alone, they assign to him a second person in himself and with himself…producing out of himself the beginning of all things.” —Tertullian, Against the Valentinians, Chapter 7

This is the same process he would call prolatio and apply to the Trinity in Against Praxeas, explicitly crediting Valentinus as his source. The admission was unavoidable—it was his response to his critics who recognized exactly what he was doing.

This is a direct link between the Christian Trinity’s prolation teaching and its Gnostic source, as confessed by Tertullian himself—the man who gave Trinitarians, even today, their framework: “one substance in three persons.”

Confession Two: The Majority of Believers Were Startled

“The simple, indeed, who always constitute the majority of believers, are startled at the dispensation of the Three in One, on the ground that their very rule of faith withdraws them from the world’s plurality of gods to the one only true God.” —Tertullian, Against Praxeas, 3.

The majority of believers in Tertullian’s day recognized his doctrine as resembling the world’s plurality of gods. They knew the Shema commanded ‘one He,’ not three Hes. If the Trinity had always been believed, why would introducing it startle the majority?

Confession Three: He Explicitly Rejected Jewish Monotheism

“This doctrine of yours bears a likeness to the Jewish faith…so to believe in One God as to refuse to reckon the Son besides him…what difference would there be between us and them?” —Tertullian, Against Praxeas, 31.

Among Tertullian’s stated justifications for the Trinity was the aim of distinguishing Christianity from Judaism. The one God of the Jews—the Shema, the standard Jesus affirmed—was a problem he felt needed to be solved.

Scholarship Confirms the Gnostic Source

“Surprising though it may seem, there is total agreement among scholars on at least one point. Adolf von Harnack, Ignacio Ortiz de Urbina, Luis M. Mendizabal, George Leonard Prestige, Peter Gerlitz, Ephrem Boularand, John Norman D. Kelly, Frauke Dinsen, Christopher Stead—all without exception agree in claiming that the Gnostics were the first theologians to use the word homoousios, or at least that before the Gnostics there is no trace at all of its existence. The late Aloys Grillmeier wrote: ‘The early history of the Nicene homoousios shows us that the theologians of the church were probably made aware of this concept, and thus of the doctrine of emanation, by the Gnostics.’” —Beatrice.

As documented above, Tertullian stole the idea of emanations from Valentinus. This scholar just connected that same act to the source of the doctrine of homoousios, and that by a noteworthy “total agreement among scholars.” It was within this same framework that Tertullian also translated the Greek Gnostic word trias into the Latin trinitas, giving us the English word Trinity. The entire confession—“a Trinity of one substance in three persons”—traces directly to pagan and Gnostic sources. Not one word of it is biblical.

Scholarship Also Confirms the Stoic Philosophical Source

Tertullian is famous for publicly despising philosophy. In Prescription Against Heretics, he demands to know what Athens has to do with Jerusalem, and what the Academy has to do with the Church, naming the philosophers themselves as the fathers of the heretics. He presents himself as a defender of simple, unphilosophical faith against pagan speculation. Biblically, this is what wolves in sheep’s clothing look like: outwardly presenting themselves as holding biblical principles while imposing pagan philosophy as truth.

Yet the very metaphysics underlying his Trinitarian formula is borrowed directly from Stoic physics. In On the Flesh of Christ, Tertullian states the basis of his entire system:

“Everything that exists is body of some kind or another. Nothing is incorporeal except what does not exist.” —Tertullian, On the Flesh of Christ, 11.

This is not biblical language. However, it is the foundational claim of Stoic ontology as the Stanford Encyclopedia of Philosophy summarizes:

“According to the Stoics, only bodies exist, because only bodies have the capacity to act or be acted upon (Cicero, 45A; Sextus, 45B, Nemesius, 45C)… In accord with their ontology, the Stoics make God a corporeal entity, identical with the active principle. God is further characterized as eternal reason (logos: Diogenes Laertius, 44B) or intelligent designing fire or breath (pneuma) which structures matter in accordance with its plan (Aetius, 46A).” —Stoicism, Stanford Encyclopedia

Note carefully: in Stoic philosophy, logos is not merely God’s spoken word or a title for a distinct divine person—it is the corporeal substance of God himself. This is the conceptual background Tertullian inherited in the world and applies it to the Father-Son relationship. This is not a biblical category of “Word” but a pagan category of shared divine-body material.

Here is what we can say without reservation: Tertullian’s defense of the Trinity depended on philosophical assumptions about substance and corporeality that are nowhere taught by the apostles. While Tertullian frequently appealed to Scripture, on this particular point he did not demonstrate that these metaphysical categories were inherited from the apostles themselves. Instead, he defended them as true through philosophical reasoning and argued that “heresy has rather taken it from truth” (Against Praxeas, c.8). He made no attempt to show that these concepts had been handed down by Jesus, the apostles, or the earliest believers.

To the contrary, Justin Martyr had affirmed that God is incorporeal and beyond all naming, writing that “the ineffable Father and Lord of all neither has come to any place, nor walks, nor sleeps, nor rises up, but remains in His own place… having neither eyes nor ears, but being of indescribable might” (Dialogue with Trypho 127). Elsewhere, he describes Christians as those who “have dedicated ourselves to the unbegotten and impassible God” (First Apology 25). Droge summarizes Justin’s Platonic inheritance on this point as the claim that God is “immutable, impassible, incorporeal, and nameless” (Droge, 306).

Likewise, Irenaeus had explicitly defended an indivisible, non-compound God: “The Father of all is not to be regarded as a kind of compound Being…but Nous [mind] is the Father, and the Father Nous” (Against Heresies, 2.17.7).

These were not fringe positions. They were the mainstream (orthodox and majority) assembly’s understanding before Tertullian wrote in opposition to it. Tertullian himself acknowledged as much in his second confession above. The majority of believers were not modalists; they were instinctive monotheists whose inherited teachings had impressed upon them the unity and simplicity of God. Their recoil from Tertullian’s “three persons” language was, at its root, the same intuition Justin and Irenaeus had expressed philosophically: that God is indivisible, non-compound, and incorporeal. Tertullian’s Stoic answer to that majority—that real substance could proceed from God because God is corporeal—was precisely what neither the apostles, nor his predecessors, nor the majority of believers had ever taught.

The problem is compounded by the fact that Tertullian, Justin Martyr, and Gregory of Nyssa did not claim that their doctrine of multiple persons within God was inherited from Jewish monotheism. To the contrary, they clearly and repeatedly argued that the Jews failed to perceive the distinctions they believed existed within the Godhead.

This makes the modern claim that the doctrine of multiple persons within God originated from Jewish monotheism problematic. The very theologians advancing that doctrine explicitly presented it as something the Jews themselves did not recognize.

So the man who scorned Athens built his doctrine of God on Athens’s own premises—specifically on Stoic physics, a debt he never once acknowledged. Paul warned, ‘as the serpent beguiled Eve through his subtlety,’ and Tertullian fits the warning precisely.

Paul Tillich Defends the Rebellion

Modern Trinitarian scholarship openly acknowledges this debt, where Tertullian himself would keep it under wraps. On the Logos doctrine specifically, Paul Tillich—regarded as one of the most influential Trinitarian theologians of the twentieth century—is direct:

“Christianity took from its great competitor [the Stoics] many fundamental ideas. The first is the doctrine of the Logos, a doctrine that may bring you to despair when you study the history of trinitarian and christological thought. The dogmatic development of Christianity cannot be understood without it.

“Logos means ‘word.’ But it also refers to the meaning of a word, the reasonable structure which is indicated by a word. Therefore, Logos can also mean the universal law of reality. This is what Heraclitus (late 6th/early 5th-century BC) meant by it, who was the first to use this word philosophically…” —Tillich, 7.

That is the swap: “This is what Heraclitus meant by it…” Not what Moses meant by ‘word.’ Not what Jesus meant by ‘word.’ What the pagan philosopher Heraclitus meant by it: a divine being.

Tillich says, “Christianity took from its great competitor many fundamental ideas.” Paul said, “Don’t let anyone rob you through his philosophy.” Tillich says, “The dogmatic development of Christianity cannot be understood without it.” Paul said to “teach no other doctrine.” Jude said to “Earnestly contend for the faith once delivered.” Peter said to “be established in the present truth.” The “dogmatic development” is “church-speak” for dismissing these apostolic commands and justifying adopting pagan philosophy in place of biblical revelation.

Recognizing the contrast between the Stoic logos, which has corporeal reality, and the biblical ‘word’ given to man from outside himself is foundational to restoring John’s Prologue to the Biblical concept of ‘word’ from the pagan reading imposed on it since Justin Martyr, a recovery we will take up in detail in Chapter Fourteen.

For now, we are dealing with exposing the pagan foundations of the categories of thought that led to the development of the Trinity. We continue now with Tillich’s admission of the swap from an Old Testament view of word to a pagan view of word. Let’s read the whole quote in context, and then break it down:

“If one thinks in Old Testament terms, one would prefer to translate logos by ‘word;’ if one thinks in Greek terms, as the [Trinitarian] Apologists did… then one would translate logos by… the meaningful structure of reality.
“As the immediate self-expression of the divine, the Word (the Logos, form, or reason) is less than the divine abyss, because the divine abyss is always the beginning, and out of the depths of divinity his self-manifestation toward the world comes. The Logos is the beginning of the generations of God; he has, so to speak, a diminished transcendence or divinity. But if this is so, how can he reveal God fully? This became a problem for later times. As soon as the Apologists used the term ‘logos’ the problem arose and could not be silenced any more. If the logos is the self-expression of God in movement, is he less than God or fully God?… The difficulty was not the incarnation as such. ‘Incarnation’ is one of the most ordinary events in Greek mythology and in all mythology. Gods come to earth; they take on animal, human, or plant form; they do certain things and then return to their divinity. Such a concept, however, could not be accepted by Christianity. The difficulty was that this Son of God, who was a historical man and not a mythical figure, is supposed to be the absolute and unique incarnation of God.” —Tillich, 31-32.

Notice what Tillich just did. To begin with, he just admitted that there are two ways to interpret dabar/logos/word. He first admits that the Old Testament view is simply ‘word.’ Then he admits the view adopted from philosophy by the Apologists carries the complex baggage going back to Heraclitus. Just for reference, Moses gave Israel the Law ~7-10 centuries before Heraclitus was born; Plato came later still. Both of whom predated Jesus by ~3-4 centuries.

What is important for us is this: Where does the Bible say, demonstrate, or imply that “word” means “the meaningful structure of reality”? It does not. Tillich himself admitted it. He clearly said that in Old Testament terms, words like dabar (Hebrew) and memra’ (Aramaic) simply mean ‘word.’

The question Tillich is wrestling with is, “If the logos is the self-expression of God in movement, is he less than God or fully God?” But this is not a question the Bible ever asked or needed to answer. It is, however, the exact question Numenius and Plotinus were asking about their triune divine hierarchy.

Hebrew/Greek word: Dabar/Memra’/Logos Usage
Bible:	“Word”
Philosophy:	“Word,” and “meaningful structure of reality,” and “divine nature emulated by substance from the first cause,” etc.

It isn’t until these words are viewed through the gods of the pagans that they take on the extra philosophical baggage he is justifying here. Where does the Bible say to ‘go back to Aristotle to understand the concepts by which to understand the God of the Bible’? Is it really so difficult to see the error in going to the gods around them to define the God of the Bible?

The pagan philosophical framework generated that question for the philosophers, and once the false logos equation/connection was made, Christian theologians were “snared” [God’s word] within it—forced to answer a pagan question using pagan categories, because they had accepted a pagan premise. Tillich, writing in the twentieth century, is still inside that snare. He is not just describing what the Apologists did—he is congratulating it, doing it himself, and calling it necessary. This is precisely the complexity Paul warned against being moved away from. It is the opposite of the simplicity of Christ. Tillich was aware that the Apologists adopted pagan concepts and defended doing so as necessary:

“If you read Harnack’s History of Dogma, you will see how the great creeds…came into existence…You will see that the ecumenical councils of Nicaea and Chalcedon used a lot of terms from Greek philosophy in formulating the Trinitarian and Christological dogmas. Harnack saw in this development a second wave of Hellenization. The first wave was Gnosticism, and the second wave was the formulation of the ancient dogma [i.e. the Trinity]. The first was rejected by the church; the second was accepted and used by the church…Harnack was right in saying that Hellenization had taken place, but wrong in defining this as intellectualization. According to Harnack, a foreign element entered into Christianity when terms like ousia and hypostasis were used in constructing the official [Trinity] dogma of the church. This process began… in the apostolic fathers [i.e. Justin Martyr]… All this can be called Hellenization, but how else could it have happened?… Harnack’s greatness is that he showed this process of Hellenization. His shortcoming was that he did not see the *necessity* of it…I would not accept the idea which one hears so much that all the Greek elements must be thrown out…If this were done consistently…it would rule out the whole history of doctrine (dogma).” —Tillich, 515-519.

There it is—Tillich’s own word: necessity. He criticizes Harnack for not seeing the necessity of what God explicitly forbade: making common cause with Christianity’s enemies. What God called rebellion, what Paul called robbery, this Trinitarian scholar calls a necessity. And then, by saying that throwing out the Greek elements “would rule out the whole history of doctrine,” he is openly admitting that the entire extrabiblical doctrinal structure—including the Trinity—cannot stand without its pagan philosophical foundation.

He is not defending a biblical doctrine. He is defending a structure that subjects Scripture to philosophy by making pagan philosophy the authority for interpreting Scripture. That is the admission this whole book has been building toward.

Centuries after Clement of Alexandria called philosophy ‘necessary… to Exegesis,’ modern Trinitarian scholar Paul Tillich uses the identical word about this same Stoic borrowing: “The dogmatic development of Christianity cannot be understood without it.”

Tertullian’s Stoic corporeality provided the substance behind Tillich’s “necessity.” Without it, Tertullian admitted, the two-person structure collapses.

“Do you then, (you ask,) grant that the Word is a certain substance, constructed by the Spirit and the communication of Wisdom? Certainly I do. But you will not allow Him to be really a substantive being, by having a substance of His own; in such a way that he may be regarded as an objective thing and a person, and so be able (as being constituted second to God the Father,) to make two, the Father and the Son, God and the Word.” —Tertullian, Against Praxeas, Chapter 7

Tertullian’s own logic confirms it: distinct divine persons first require a substance that can be divided. He ridiculed his opponents for rejecting this. But remove the Stoic-sourced premise of corporeality he was “introducing,” and, as he himself admitted, the Trinity’s internal architecture falls. Tertullian’s Stoic corporeality not only provided a new foundation for building the Trinity on, but also explained why corporeality was necessary and what it accomplished. We will take this up again in Chapter Twelve.

“For no one can lay any other foundation than that which has been laid, which is Jesus Christ.” (1 Corinthians 11:3).

Scholarship Also Confirms the Schismatic Source

Tertullian faced a theological crisis and chose Valentinus over Scripture.

Modalism—the teaching that the Father and Son are the same person appearing in different modes—had emerged as a reaction to Justin Martyr’s Logos theology, which had introduced the ‘disturbing’ novelty of a second God.

Writing against Praxeas, Tertullian says:

“Praxeas….was the first to import to Rome out of Asia this kind of wrong-headedness [“that the Father…himself is Jesus Christ”]…” —Tertullian, Treatise Against Praxeas, Par. 1

Hippolytus provides a second witness to the claim that modalism was a new invention in their day. Writing against Noetus, he says:

“This person was greatly puffed up and inflated with pride, being inspired by the conceit of a strange spirit. He alleged that Christ was the Father Himself, and that the Father Himself was born, and suffered, and died. You see what pride of heart and what a strange, inflated spirit had insinuated themselves into him.” —Hippolytus, Against Noetus, chap. 1

It is inconceivable that either Tertullian or Hippolytus would frame Modalist doctrine—or, for that matter, anything even close to it—as novel and prideful if it had simply been the majority belief. Such a claim would have worked against them, not the Modalists, had it been false. But the reverse was the case. Tertullian’s and Hippolytus’ writings were very effective in refuting and ending the fifty-year, short-lived (180–230 AD) popularity of modalism.

Modalists like Noetus and Praxeas had reacted to Justin’s ditheism by concluding, “If Jesus is God, then he must be the Father.” Tertullian needed to refute that novel conclusion. But here is what he never did: he never turned to Scripture and the apostles to establish his counter-position. He turned to Valentinus the Gnostic and justified his novel view by appealing to his own human reasoning (as previously noted).

Justin’s theft from pagan philosophy generated a modalist overreaction; Tertullian answered that imagination with another theft from paganism, itself an overreaction on the other side of the ditch.

Even more telling is the context in which Tertullian was writing: his loyalty to Montanism, a heresy he aligned with. Praxeas, according to Tertullian, had prevented the Bishop of Rome from recognizing the Montanist prophecy. Tertullian attacks him as a Monarchian and develops a new, unique doctrine of the Trinity, yet one that still holds that there was a time when the Son was not. The famous Tertullian line—that Praxeas “drove away prophecy and brought in heresy; he put to flight the Paraclete [referring to Montanism], and he crucified the Father”—is thus a double accusation: doctrinal and ecclesiastical. His attack on Praxeas was also a form of revenge for the suppression of Montanism’s “New Prophecy.”

“In the treatise Against Praxeas, he [Tertullian] defends and articulates trinitarian belief, insisting on continuity between his recent defense of the Paraclete and the older Rule of Faith… Thus, what was to become ‘orthodox’ Christian theology depended on the ‘heretical’ New Prophecy at this particular place and time.” —McGowan, 437–457.

This scholar’s finding is significant: the doctrinal development of the Trinity in Carthage was inseparable from Montanist sectarianism. One heresy, Montanism, in rejecting another heresy, Modalism, resorted to yet another heresy, Gnosticism, to provide the vocabulary for its own emerging heresy, the Trinity, with its key concepts and terms.

Once again, human reasoning—elevated above Scripture—was the instrument used to dismantle God’s commanded belief in “one He.”

If anyone ever fit Paul’s warning against being robbed by philosophy, Tertullian did. Sadly, by his day, philosophy had changed from being warned against to being embraced and considered necessary. Even by a man who continued to denounce philosophy as the father of all heresies.

Summary—In this chapter, I have documented:

✦ That Tertullian coined the Trinitarian formula and admitted deriving it from Valentinus, the Gnostic.

✦ That his source from Valentinus was defended not by Scripture or apostolic precedent, but by his own philosophical reasoning—with no attempt to show the apostles taught it.

✦ That there is total agreement among scholars that the Gnostics were the first to use homoousios—the same word Constantine would impose at Nicaea.

✦ That the word Trinity itself traces through Gnostic usage via Tertullian’s translation of trias into trinitas.

✦ That Tertullian condemned philosophy as the father of all heresies, but hypocritically embraced the Stoic view of corporeality.

✦ That Justin Martyr, Irenaeus, and the majority of believers before Tertullian all affirmed God’s incorporeality — the very position Tertullian’s Stoic corporealism contradicted.

✦ That modalism—the theological crisis Tertullian was responding to—was itself a new invention, as Hippolytus documents when he frames Noetus’ doctrine as novel and prideful, a framing that would have backfired had modalism been the majority belief.

✦ That modalism’s popularity arose as an overreaction to Justin Martyr’s implied second God, and that Tertullian’s Gnostic-derived formula was a counter-overreaction in the opposite direction—two ditches flanking the narrow biblical road of “one He.”

✦ That Tertullian’s formulation of the Trinity was a product of sectarian revenge as much as theological conviction, inseparable from his Montanist loyalties.

✦ That mainstream scholarship confirms this entanglement—McGowan documents that what became ‘orthodox’ Christian theology depended at this critical moment on the ‘heretical’ New Prophecy of Montanism.

✦ That the majority of believers in his own day were startled by his formula and recognized it as resembling the pagan plurality of gods.

✦ That Tertullian explicitly stated that his unpopular view of multiple persons in ‘one substance’ (una substantia) served to distinguish Christianity from Jewish monotheism.

✦ That Tertullian’s own Trinity was not even the later Nicene version—he held that there was a time when the Son was not, the same as Arius, making him closer to what Nicaea would later condemn as ‘heresy’ than to the orthodoxy that has since claimed him.

Tertullian’s theology, by the testimony of his own words and Trinitarian scholars, continued the evolution away from the Biblical ‘one He.’ Tertullian thus sided with the rebellion in overthrowing and redefining God’s first and greatest commandment on man’s terms rather than God’s.

The majority of believers in Tertullian’s own day recognized the deception. You are not alone in seeing it now. But seeing isn’t enough—choosing is not optional.

Deuteronomy 30:19–20: “…I have set before you life and death, the blessing and the curse. Therefore choose life, that you may live, you and your descendants, to love Yahweh your God, to obey his voice, and to cling to him; for he is your life…”

As we shall see in upcoming chapters, the pattern Tertullian established at Carthage would repeat itself a century later at Nicaea—the same sectarian rivalry, the same going beyond what is written, but ultimately with Roman emperors enforcing the outcome.

Will you side with Satan’s legal heirs in the rebellion against ‘one He’? Or will you reject the subtlety of deceit and choose the life God intended for you?

“If you love me, keep my commandments” means trusting God over either Satan or human reasoning to the contrary.

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