Marcion of Sinope (c. 85–c. 160)

A bishop’s son on the shores of Pontus Euxinus

Marcion’s origins are poorly documented, as is often the case for figures described only by their adversaries^[1]. Tradition places his birth around 85 in Sinope, a Greek city of Pontus, on the southern coast of the Black Sea—the present-day Sinop in Turkey^[2]. It was a world of maritime trade, at the crossroads of the Greek world and the Scythian steppes, which Tertullian describes with pointed disdain: if he is to be believed, the nations of Pontus would be wild peoples spending their lives in wagons, without fixed dwellings, leading an existence foreign to all civilization^[3].

According to Epiphanius of Salamis, writing in 374-377 in his major anti-heretical work the Panarion, Marcion was "an ascetic and the son of a bishop of our holy Catholic Church"^[4]. This bishop was, according to a late tradition, a certain Philologos of Sinope. The same Epiphanius recounts a famous anecdote: as an adult, Marcion allegedly seduced a consecrated virgin, "deceiving her hope, thus degrading both her and himself," which earned him excommunication by his own father^[5]. Several modern historians doubt the factual value of this story and see it as a metaphor: the Church, an incorruptible "virgin," was "seduced" and corrupted by Marcion’s heresy, a narrative later historicized literally by Epiphanius two centuries later^[6]. Whatever the truth of this episode, ancient tradition agrees on one solid point: Marcion left Pontus under circumstances of rupture, not mere commercial migration.

The shipowner who came to Rome

Rhodon, a Christian author of the late 2nd century, and Tertullian himself respectively call him a "sailor" and "shipmaster" (nauclerus)^[7]. Marcion was therefore not an obscure itinerant preacher: he was a wealthy businessman, whose profession—the outfitting of merchant ships on the Black Sea and then the Mediterranean—explains both his wealth and mobility. Between 135 and 140, he left Pontus for Rome, then the administrative and soon intellectual heart of Western Christianity^[8].

Upon arrival, he joined the Roman Christian community and made a considerable donation: 200,000 sesterces^[9]—at the rate of legionary pay in force since Domitian (300 denarii per year, i.e. 1,200 sesterces), more than 160 years’ pay for a common legionary^[10]. This gesture was no trivial matter: it revealed a man eager to quickly gain influence in the Church of the capital, and partly explains the severity of the ensuing rupture—a gift of such magnitude publicly returned amounts to a declaration of theological war.

Cerdon and the break of autumn 144

It was in Rome that Marcion met, according to Saint Irenaeus of Lyon, a certain Cerdon, who came from the East and was linked to the movement originating with Simon Magus^[11]. Cerdon already taught that "the God proclaimed by the Law and the prophets is not the Father of our Lord Jesus Christ": the former was known, the latter unknowable and good^[12]. Hippolytus of Rome confirms this lineage in his Refutation of All Heresies: "Marcion confirmed the teaching of this heretic [Cerdon]"^[13], before systematizing it and giving it its most radical and lasting form in his great treatise, the Antitheses.

The break between Marcion and the Roman Church occurred in autumn 144^[14]. Rome, then governed by a succession of bishops including Pope Pius I, rejected the doctrine of two gods: Marcion was formally excommunicated, and his 200,000 sesterces were returned—a gesture which, in the ancient world, amounted to publicly breaking all communion, even materially. Far from submitting, Marcion then founded his own Church, organized parallel to the Catholic Church with its own bishops, liturgies, and scriptural corpus—the first major ecclesiastical schism in Christian history to leave such well-documented traces.

"I recognize the firstborn of Satan": the legend of Saint Polycarp

A famous encounter in Christian memory pits Marcion against a direct disciple of the Apostles, Saint Polycarp of Smyrna, who was passing through Rome. According to the account reported by Saint Irenaeus — who himself regarded Polycarp as his teacher in his youth — Marcion came to him and asked: "Do you recognize me?"

"Polycarp himself answered Marcion, who met him once and said to him: 'Do you recognize me?' — 'I recognize you, yes: the firstborn of Satan.'" — Saint Irenaeus of Lyons, Against Heresies, Book III, Chapter 3, § 4^[15]

This sharp retort, handed down firsthand by a witness of the next generation, illustrates the seriousness with which the apostolic Church judged the Marcionite system: not as a tolerable variant of the faith, but as its radical negation. It is fully understood only in light of what Marcion actually taught — a system that must now be presented in its own coherence before exposing its flaws.

To refute a system, one must first present it honestly, in its strongest form. Marcionism was neither absurd nor crude: it was a rigorous — though ultimately destructive — attempt to answer a genuine question, one that troubles every believer confronted with evil and the severity of certain Old Testament narratives: how can the God who commands the extermination of the Canaanites be the Father revealed by the merciful Christ?

The Demiurge and the alien God

The heart of the Marcionite system rests on a distinction between two divine principles. The first is the Creator (Demiourgos), the God of Israel, author of the material world, legislator of Sinai, just according to a strict and vindictive justice — "an eye for an eye, a tooth for a tooth"^[16]. The second is the alien God (Deus alienus), who remained completely unknown to any creature and prophecy until He manifested, without preparation or announcement, in Jesus Christ, under the reign of Emperor Tiberius^[17].

Irenaeus summarizes the thesis in a clear formula: according to Marcion, "the one who was preached by the Law and the Prophets is not the Father of our Lord Jesus Christ"^[18]. The Demiurge, whom Marcion also calls the Cosmocrator — the "ruler of the world" — is neither evil in an absolute sense nor malevolent: he is only inferior, limited to his own justice, and ignorant of the existence of the superior God before the eruption of Christ on his territory^[19].

"He was unknown and had to remain so": a radical hatred of the Old Testament

From this dichotomy flows a total rejection of the Old Testament, which Marcion considers the authentic — but inferior — revelation of the Demiurge alone, with no prophetic value regarding Christ. Contrary to the entire Christian tradition, which reads the Jewish Scriptures as a providential preparation for the Gospel, Marcion sees them as the closed work of a god alien to true salvation. The Messiah announced by the Jewish prophets, he insists, is not Jesus: he is a warrior king still awaited by the Jews, consistent with the Demiurge alone — Jesus belongs to an entirely different order^[20].

The very name of his system plays on a strongly marked philosophical opposition in antiquity between the old and the new. According to Tertullian, the novelty of Marcion’s god even turns against him:

"God, if he is old, loses the eternity that is to come; if he is new, the eternity that has passed. Novelty testifies to a beginning." — Tertullian, Against Marcion, Book I, Chapter 8^[21]

A ghost Christ: the docetic Christology

Since matter is the work of the inferior Demiurge, Marcion cannot admit that Christ, sent by the alien and good God, took on true human flesh — that would sully the superior God by mixing Him with creation He did not make. His Christology is therefore docetic (from the Greek dokein, "to seem"): Christ was not born of the Virgin Mary, has no genealogy, and appears suddenly, adult, in the synagogue of Capernaum, in the fifteenth year of Tiberius^[22]. His flesh is only an appearance; his passion and death mere simulacra.

Tertullian summarizes this doctrine with biting irony:

"His Christ, to avoid all these deceptions and impostures [of the flesh]… was not what he appeared to be, and pretended to be what he was not — incarnate without flesh, human without being man." — Tertullian, Against Marcion, Book III, Chapter 8^[23]

The stakes are high: if Christ does not have true flesh, He did not truly suffer, did not truly die, and therefore was not truly resurrected. Christian salvation — Christ’s victory over death in His own flesh — collapses. This is precisely what the Catechism of the Catholic Church will recall eighteen centuries later: "The first heresies denied less the divinity of Christ than his true humanity (gnostic docetism)"^[24].

A morality of fleeing from the flesh

From this devaluation of matter flows a radical ascetic morality. Baptized Marcionites commit to total continence; marriage, which perpetuates the flesh and populates the Demiurge’s kingdom, is discouraged, if not forbidden to the most fervent^[25]. Fasting is intensified — notably, according to the Council of Braga, the refusal to honor with joy the day of Christ’s Nativity "according to the flesh," which they prefer instead to fast, precisely because they do not believe that Christ "was born in the true nature of man"^[26]. This morality, seemingly austere and demanding, attracted many faithful seeking a Christianity perceived as purer than that of the Great Church, judged compromised with the world.

The First Competing "New Testament" in History

Marcion’s most consequential innovation was not only doctrinal but scriptural. The first to deliberately and definitively assemble an alternative authoritative corpus of Christian texts—what historians today call a “canon”—was very likely Marcion himself^[27]. His corpus, called his Instrument (Instrumentum), included only eleven books^[28]: a single gospel, the Evangelikon, and a collection of Pauline letters, the Apostolikon.

This project was accompanied by a doctrinal treatise, now lost, the Antitheses—a work of systematic contrasts between passages from the Old Testament and the words of Christ, intended to visually demonstrate the incompatibility of the two Covenants^[29]. Although the original text has not survived, the many quotations by Tertullian allow the reconstruction of several characteristic oppositions^[30]:

Here the reader sees Marcion’s rhetorical strategy: isolating Old Testament verses from their narrative and theological context to oppose them term by term to gospel maxims presented outside any Jewish context. This is a method of selective reading—the fundamental error that the entire Catholic Tradition, from Justin to Augustine, sought to dismantle by restoring the unity of the economy of salvation.

The Evangelikon: Luke Cut with a Knife

The gospel chosen by Marcion is a condensed version of the Gospel according to Saint Luke, stripped of its first two chapters—genealogy, annunciation, nativity, childhood—deemed incompatible with a Christ without true flesh or Jewish ancestry^[31]. The remaining text is further edited: every positive reference to the fulfillment of Jewish prophecies, every favorable mention of the Law or the Prophets, is removed or altered^[32].

Tertullian heaps a famous sarcasm on Marcion, comparing his editorial work to that of a rodent:

“What Pontic rat ever had such power to gnaw as the one who gnawed the Gospels to pieces?” — Tertullian, Against Marcion, Book I, Chapter 1^[33]

Notably, Marcion assigns no author to his gospel—neither Luke nor anyone else. Tertullian ironically notes: “He assigns no author to his Gospel, as if he were not permitted to affix a title to what, in his eyes, was no crime to subvert even the body”^[34]. This deliberate absence of authorship sharply contrasts with the apostolic tradition’s insistence on precisely naming the author of each gospel, guaranteeing its authority and fidelity to the testimony of the Twelve.

The Apostolikon: Ten Letters of Paul, the Sole Apostle

Marcion regarded Saint Paul as the only true apostle of Christ, the one who alone understood the radical break between the Law and the Gospel—the Twelve, in his view, remaining captive to Judaizing attachments^[35]. His Apostolikon includes ten Pauline epistles (Galatians first, then 1-2 Corinthians, Romans, 1-2 Thessalonians, Ephesians—called “to the Laodiceans”—Colossians, Philippians, and Philemon), purged of all passages favorable to the Creator or the Old Testament^[36]. He excludes the pastoral epistles (1-2 Timothy, Titus), the Epistle to the Hebrews, the Catholic epistles, the Acts of the Apostles, and the Apocalypse—that is, all texts linking nascent Christianity to Israel’s history or the collegial authority of the Twelve^[37].

This textual manipulation did not escape the Church’s vigilance: the Muratorian Fragment, the oldest known list of books received by the Church of Rome (late 2nd century), explicitly denounces a false “Epistle to the Laodiceans” circulating “under Paul’s name, to support Marcion’s heresy,” and formally refuses to receive it into the Catholic canon^[38]. This is one of the earliest direct testimonies of a scriptural canon defined against a specific Marcionite forgery.

A Lost Work Reconstructed by Its Opponents

No complete copy of Marcion’s Instrumentum has survived. All we know about it paradoxically comes from its opponents: Tertullian quotes it extensively in his Books I and IV Against Marcion^[39], and especially Epiphanius of Salamis, in his Panarion (374-377), meticulously identifies seventy-eight passages of the Marcionite New Testament he judges falsified compared to the received text^[40]. This is an impressive work of patristic philology, methodologically comparable to a modern critical edition—carried out fifteen centuries before the invention of scientific textual criticism.

To understand the severity with which Marcion was received by his contemporaries, one must appreciate the density and promptness of his refutation: no heresiarch prior to Arius provoked such abundant, rapid, and convergent anti-heretical literature.

Justin Martyr: the first witness, during Marcion’s lifetime

The very first written testimony about Marcion comes from Saint Justin Martyr, a converted philosopher and apologist, in his First Apology, addressed to Emperor Antoninus Pius around 150-155 — therefore during Marcion’s own lifetime:

“There is Marcion, a man from Pontus, who is still alive today and teaches his disciples to believe in another god, greater than the Creator.”
— Saint Justin Martyr, First Apology, chapter 26^[41]

Justin adds that Marcion, “by the help of demons,” caused followers “from every nation” to utter blasphemies denying that God is the creator of the universe^[42]. This testimony is crucial on several levels: it attests that Marcion’s success was rapid — barely a decade after his break with Rome, his doctrine had already spread across several provinces of the Empire — and that the Church immediately classified him, like other major Gnostic systems of the time, among the most dangerous counterfeiters of the Christian name. Justin may even have dedicated a specific treatise to him, the Syntagma against all Heresies, now lost but attested by later authors^[43].

Irenaeus of Lyon: apostolic succession and the Rule of Faith

Saint Irenaeus of Lyon, a disciple of Polycarp who himself witnessed the encounter with Marcion, devotes several chapters of his major treatise, Against Heresies (circa 180), notably chapter 27 of book I already cited, to his refutation. His fundamental argument is not only doctrinal: it is ecclesiological. Irenaeus opposes Marcion’s alleged novelty with the continuity of apostolic succession and the unity of the Rule of Faith, professed “by the Church, though scattered throughout the whole world”^[44]:

“One [only] God, the Father Almighty, creator of heaven, earth, sea, and all things that are in them; and one Christ Jesus, the Son of God, incarnate for our salvation; and the Holy Spirit.”
— Saint Irenaeus of Lyon, Against Heresies, book I, chapter 10, § 1^[45]

This formula, nearly a century and a half before the Council of Nicaea, attests that the Church already confessed, well before any formal conciliar definition, the unity of the Creator God and the Savior God, and the reality of the incarnation — the two precise points Marcion denied. Thus, it is not an isolated theologian responding to Marcion: it is the faith consciousness of the entire Catholic Church, attested in a profession received “everywhere in the world.”

Tertullian: five books to dismantle a system

The most systematic refuter of Marcion remains Tertullian, whose Adversus Marcionem, written and revised between 207 and 212, constitutes one of the most extensive anti-heretical treatises in ancient Christian literature — five entire books against a single adversary^[46] (Saint Augustine would later write, against the Manichaean Faustus, an even longer treatise, in thirty-three books^[47]). Tertullian himself dates Marcion’s appearance “in the time of Antoninus Pius,” about one hundred and fifteen years after the revelation of Christ under Tiberius^[48] — a chronology he turns against his opponent: a truly supreme God could not remain unknown for more than a century of Christian life before manifesting through an isolated heresiarch from the remote Pontus.

Three decisive philosophical arguments against dualism

Beyond the polemic, Tertullian develops three rational arguments that remain, eighteen centuries later, the framework of all Catholic refutations of dualism:

These three arguments converge on the same conclusion: Marcionite dualism does not solve the problem of evil, it displaces it by multiplying it — instead of one God who is both just and merciful, one must now explain the coexistence of two competing principles, which is philosophically more costly, not economical.

Hippolytus and the Greek, non-Christian ancestry of the system

A decisive contribution comes from Hippolytus of Rome, in his Refutation of All Heresies (circa 222-235). Rather than merely discussing the doctrine itself, Hippolytus seeks its real intellectual source — and finds it not in the Gospel, but in a pre-Christian Greek philosopher:

“[Marcion] formed and shaped the same opinions [as Empedocles] — namely that there are two causes of the universe, discord and friendship […]. The true author of this system is Empedocles, son of Meton, from Agrigentum.”
— Hippolytus of Rome, Refutation of All Heresies, book VII, chapters 17-18^[52]

Empedocles of Agrigentum (5th century BC) indeed taught a cosmology based on two opposing forces, Friendship (Philia) and Discord (Neikos), which alternately unite and separate the four elements. Hippolytus thus demonstrates that Marcion’s dualism has nothing of an authentic Christian revelation: it is a preexisting pagan cosmology, simply rebranded in evangelical language and overlaid onto Christianity. The argument holds: what Marcion presented as the restoration of the pure Gospel is, historically, only a syncretism borrowed from early Greek philosophy.

A Parallel Church Spanning the Empire

Unlike other short-lived sects of antiquity, the Marcionite Church founded after 144 experienced real and lasting expansion. It established bishops, martyrs, and organized communities that persisted long after the death of its founder around 160.

Spread in the East and Gradual Dissolution

In the West, the Marcionite Church died out fairly quickly, in just under three centuries after the break of 144^[62]. In the East, however, it survived much longer: in the 4th century, Epiphanius still attests to its presence in Egypt, Palestine, Arabia, Syria, Cyprus, the Thebaid, and even Persia^[63]. Christian emperors, beginning with Constantine, forbade Marcionite worship both publicly and privately^[64], accelerating its decline without immediately extinguishing it: residual Marcionite communities persisted in some places until the 7th century, before gradually merging into other dualistic movements, some elements of whose textual corpus were later adopted by the Paulicians^[65]. It was in this same Eastern dualistic milieu, transmitted and transformed over several centuries, that another major two-principle system would later take root — that of Mani — whose name Denzinger would associate, as we shall see, with Marcion’s in a single conciliar condemnation.

Harnack’s Thesis: “The Luther of the Second Century”

At the turn of the 20th century, the German Protestant historian Adolf von Harnack devoted a now-classic monograph to Marcion, Marcion: The Gospel of the Alien God^[66]. Harnack advanced a bold thesis: Marcion was the first systematic biblical theologian of Christianity, a “Luther of the second century” seeking to purify the Gospel from all Judaizing accommodation; and it was in direct reaction to his closed canon that the Great Church was compelled, for the first time, to formally define its own corpus of books received as authoritative^[67].

The Critique of John Barton and Contemporary Historians

This interpretation has been widely revised by recent historiography. The British biblical historian John Barton, in his study Marcion Revisited, argues instead that the majority of writings now received in the New Testament already enjoyed, from the early second century, a de facto scriptural authority in much of the Church, independently of any reaction to Marcion^[68]. For Barton, Marcion’s true originality is therefore not that he pushed Christians to adopt a New Testament — this movement was already well underway — but that he forced the Church to explicitly settle the question of the Old Testament, which a portion of the nascent Christianity already accepted without formulating such a systematic theological justification^[69]. The Muratorian Fragment, which explicitly rejects a letter forged “for the heresy of Marcion”^[70], attests that the reaction to Marcion indeed played a catalytic role, without necessarily attributing to him, as Harnack did, the ex nihilo creation of the very idea of a New Testament canon.

What Catholic Tradition Teaches About the Canon

Modern historiographical debate should not obscure the constant theological principle of the Church: the two Testaments form one and the same Holy Scripture, because they proceed from one and the same God and relate to each other as promise to fulfillment. This is what the Catechism of the Catholic Church recalls in terms that explicitly target Marcion:

“The Old Testament is an indispensable part of Sacred Scripture […]. Christians venerate the Old Testament as the true Word of God. The Church has always vigorously rejected the idea of rejecting the Old Testament on the pretext that the New Testament has rendered it obsolete (Marcionism).”
— Catechism of the Catholic Church, §§ 121-123^[71]

This continuity between the two Covenants also distinguishes the Catholic position from the strictly biblical reading later adopted by some Protestant currents centered solely on the authority of Scripture (the principle of sola scriptura): for the Catholic Church, it is not only the scriptural text that guarantees its unity, but the living Tradition and the Magisterium that ensure its coherent interpretation, precisely preventing an isolated reader — a Marcion, whoever he may be — from imposing his own interpretive framework on the received corpus.

It would be inaccurate to reduce the condemnation of Marcion to a second-century episode closed with his death. The Magisterium of the Church has explicitly revisited his name for more than thirteen centuries.

Dionysius of Rome (262): Dividing the Divine Monarchy

In a letter addressed to his namesake Dionysius of Alexandria in 262, Pope Dionysius of Rome warns against those who, in the East, “divide, separate, and destroy the monarchy” — the sovereign unity of God — “into three separate powers and hypostases”^[72]. To denounce this danger, he takes precisely the Marcionite precedent as a negative reference:

“The doctrine of the senseless Marcion, who cuts and divides the monarchy [of God] into three principles, is a diabolical teaching, and not that of the true disciples of Christ.”
— Dionysius, Bishop of Rome, Letter to Dionysius of Alexandria, 262^[73]

This letter, one of the very earliest known doctrinal interventions by a bishop of Rome on a Trinitarian question, shows that a century after his death, Marcion’s name already served as a universally recognized repellent for any doctrine that fragments the unity of God — whether by dividing it into two (Marcionite dualism) or into three rival principles.

The Council of Braga (561): Anathema Against Denial of the True Flesh of Christ

Four centuries after Marcion’s death, the First Council of Braga, convened in Portugal in 561 against Priscillianist resurgences, formulates an explicit anathema associating his name with those of Cerdo and Mani:

“If anyone does not honor the day of Christ’s birth according to the flesh […] because he does not believe that Christ was born in the true nature of man, as Cerdo, Marcion, Mani, and Priscillian have said, let him be anathema.”
— First Council of Braga, Canon 4, 561^[74]

This conciliar formulation proves that the docetic denial of the true flesh of Christ — the theological heart of Marcionite error — remained, four centuries after the fact, a sufficiently living threat to justify a solemn and specifically targeted anathema.

The Council of Florence (1442): Marcion in the List of False Christologies

Nearly thirteen centuries after Marcion’s death, the Council of Florence, in its bull Cantate Domino for union with the Copts and Ethiopians (February 4, 1442), solemnly recapitulates the Church’s faith on the union of the two natures in Christ, then explicitly condemns the great heretical Christologies of antiquity:

“It anathematizes, detests, and condemns every heresy holding contrary theses. And first it condemns Ebion, Cerinthus, Marcion, Paul of Samosata, Photinus, and all who similarly blaspheme.”
— Council of Florence, Bull Cantate Domino, 1442^[75]

That Marcion’s name still appears, thirteen centuries after his death, in a solemn profession of faith of a fifteenth-century ecumenical council measures the lasting impact of his error in the dogmatic memory of the Church: it is not a closed chapter of ancient history, but a permanent temptation that each generation must recognize and reject.

Today’s Catechism: A Vigilance Still Relevant

The Catechism of the Catholic Church, published in 1992, does not merely recall the doctrinal rejection of the Old Testament (§ 123, cited above): it also explicitly links the docetism of the “first heresies” to the Church’s necessity to insist relentlessly on the true incarnation of the Son of God, “who came in the flesh”^[76]. Marcion’s name has therefore never left the living memory of Catholic catechesis: he remains the classic case that teaches why the unity of the two Testaments and the reality of Christ’s flesh are not secondary points, but pillars without which the entire edifice of salvation collapses.

The Problem of Evil, a Real Problem Poorly Resolved

The rapid and lasting success of Marcionism cannot be explained solely by the rhetorical skill of its founder. It addressed a genuine concern: how to reconcile certain Old Testament narratives of apparent severity — the wars of conquest, collective punishments, the Law and its penalties — with the tireless mercy preached by Christ in the Gospels? Marcion did not resolve this tension; he cut through it by sacrificing the unity of God rather than confronting the theological difficulty itself. Catholic theology, on the other hand, chose the more demanding — but the only coherent — path of divine pedagogy: one God who gradually leads humanity, through the history of Israel, toward the full revelation of His mercy in Jesus Christ, never contradicting Himself.

“The God of Wrath”: A Caricature That Returns Without Marcion’s Name

The Marcionite reflex never completely disappears: it resurfaces in every generation in new forms, whenever people simplistically oppose “the vengeful God of the Old Testament” to the “God of love” of the New, without realizing that this binary opposition is precisely what the Church condemned as early as the 2nd century. Some modern currents — whether stemming from poorly instructed piety, simplistic popular exegesis, or certain later esoteric systems that adopt a comparable dualism — often unknowingly repeat Marcion’s very gesture: they read the Bible as two opposing blocks instead of reading a single economy of salvation.

Catholic Response: One God, Just and Merciful

The Catholic response rests on a simple but demanding principle: justice and mercy are not two contradictory attributes of two different gods, but two inseparable facets of the one and same God. The God who gave the Law at Sinai is the very same who, in Jesus Christ, fulfills it and brings it to its fullness — not by denying it, but by revealing what it had prepared from the beginning. It is this unity, defended by Justin, Irenaeus, Tertullian, Hippolytus, and Epiphanius against Marcion, then reaffirmed conciliary from Dionysius of Rome to Florence, that the Catechism continues to teach today as an indispensable foundation of authentic Christian faith.

• The Heresies of the Early Centuries — an overview of the major doctrinal crises of early Christianity, of which Marcionism is only one chapter.
• Arius (c. 256–336) — another heresiarch whose later system denied not the unity of God but the full divinity of Christ.
• Nestorius (c. 386–c. 451) — another major Christological crisis of early Christianity.
• Did Jesus Really Exist? — the historical evidence for the existence and death of Jesus, independent of any confessional authority.
• Sola Scriptura — the Protestant principle of the exclusive authority of Scripture, to be compared with the Catholic reading of the unity of Scripture and Tradition that, as early as the 2nd century, exposed Marcion’s scriptural manipulation.