What are miaphysitism and dyophysitism?
These are questions that cut to the very heart of early Christological controversy — the great debates of the fourth and fifth centuries over how the divine and human natures relate in the Person of Christ.
The core question
Dyophysitism (from the Greek duo physis, "two natures") is the teaching that Christ possesses two distinct natures — divine and human — united without confusion in one Person. This was the position upheld by the Council of Chalcedon in A.D. 451, and it became the orthodox standard of both the Western and Eastern churches.
Monophysitism (from monos physis, "one nature") — of which miaphysitism is the more nuanced form — teaches that after the incarnation, Christ's two natures were merged or united into one composite nature, the human being absorbed into the divine. The chief proponent was the monk Eutyches of Constantinople.
The distinction between strict monophysitism (Eutyches' view that the human was swallowed up in the divine) and miaphysitism (the view held by the Oriental Orthodox churches — that Christ has "one united nature" of both divine and human, without confusion or separation) is a further refinement, though the writers in this archive treat them together under the heading "Monophysite."
How the controversy arose
Robert Young traces the origin of the dispute to the monk Eutyches, who was accused before a synod at Constantinople in A.D. 448:
Robert YoungEutyches had for seventy years lived a monastic life, and for thirty years had presided over some three hundred monks. He had hitherto been supposed to be orthodox, and the accusation took his friends quite by surprise. Eutyches had strongly opposed Nestorius, but now he was said to be in error himself, and this, too, touching the Person of our Lord.
Eutyches was pressed to explain his view:
PPAt length he said he believed our Lord, before the union of the Godhead and manhood, had two natures; but after the union only one. He was condemned. The sentence ran, "Eutyches, formerly priest and archimandrite, hath proved himself affected by the heresy of Valentinus and Apollinaris, and hath refused, in spite of our admonition, to accept the true faith."
Chalcedon: the dyophysite definition
The matter was settled — at least officially — at the Council of Chalcedon (A.D. 451), the fourth ecumenical council. Young records the formula that was adopted:
Council of ChalcedonLeo's doctrine as to the Person of Christ, is, in short, described as "two natures united without confusion, without change, and without separation, in one and the same Christ."
This is the classic dyophysite statement: two complete natures, one divine and one human, that remain distinct yet are united in a single Person.
The Monophysite opposition
But the Council of Chalcedon did not end the debate. Young describes how the Monophysite party — those holding to one nature — remained a powerful force, especially in Egypt and the East:
On the other hand, Monophysite doctrine, as put forth by Eutyches, while not denying the manhood of Christ in so many words, held that "the two natures of Christ, after the union, did not remain two natures, but constituted one nature." This was the error most prominent at the close of the century.
And the footnote that explains the term:
"the two natures of Christ, after the union, did not remain two natures, but constituted one nature."This term was now used to point out those who held that our Lord had but one nature after His incarnation.
Young explains how the controversy tore apart the professing church into warring factions:
PPThus was the professing church rent into parties at the close of the fifth century. The church and state had become so united that the emperor and the patriarch were mutually dependent upon each other for place and power.
Justinian's failed attempt to reconcile them
In the sixth century, Emperor Justinian attempted to bridge the divide. Young describes the situation:
Justinian professed to hold with the council of Chalcedon in its principal decision, that there were two natures in Christ; but his wife Theodora was a zealous Monophysite.
Young adds the defining footnote:
Those who held that Christ had but one nature, the human nature being absorbed in the divine.
Justinian's elaborate attempts to reconcile the parties — including condemning the "Three Chapters" and calling the Fifth General Council — ended in failure:
DDAThe whole scheme of the emperor was an entire failure. It in no way gained the Monophysite party back to communion with the so-called orthodox church; and in his latter days he is believed to have fallen into the very error he seemed at first so anxious to correct.
Andrew Miller's summary
Andrew Miller also covers the legacy of the controversy in his church history, noting how it spawned further theological offshoots:
Andrew MillerThe first of these, the so-called Monothelite controversy, may be described generally as a revival, under a somewhat different form, of the old Monophysite, or Eutychian, heresy. Under the general name of Monophysites are comprehended the four main branches of separatists from the Eastern church, namely, the Syrian Jacobites, the Copts, the Abyssinians, and the Armenians. ... The Monophysites denied the distinction of the two natures in Christ; the Monothelites, on the other hand, denied the distinction of the will, divine and human, in the blessed Lord.
The scriptural concern
What these writers consistently emphasize is that no human formula can fully capture the mystery of the Person of Christ. W.R.D., writing on the incarnation, states the positive truth carefully:
W.R.D.The opposite error to saying that He is two persons is to say that His two natures have combined into one. It was an ancient heresy that the two natures, Manhood and Deity, merged together. ... He is wholly Man and wholly God. He possesses all the attributes and properties of real, unfallen, holy Manhood, and at the same time possesses all the infinite attributes and properties of Deity. The unity consists, not in the amalgamation of essence, but in the Oneness of His Person.
And finally, the sobering reminder from Matthew 11:27:
His two natures have combined into one"No man knoweth the Son, but the Father." ... Clearly, it is the Incarnate Son who is unknowable. The Father, Himself, cannot explain this to us, for to understand the incarnation we would need to have the infinite understanding of the Father Himself.
In summary
Dyophysitism is the teaching that Christ has two distinct natures (divine and human) united in one Person — the position enshrined at Chalcedon and held by most of historic Christendom. Miaphysitism (a refined form of what these writers call Monophysitism) teaches that the two natures were united into one composite nature after the incarnation — the position held by the Oriental Orthodox churches (Coptic, Armenian, Ethiopian, Syrian). The strict Eutychian form — that the human nature was absorbed and swallowed up in the divine — was condemned by both sides. The writers here consistently uphold the dyophysite truth: Christ is wholly God and wholly Man, two natures without confusion, in one undivided Person — while cautioning that "no man knoweth the Son but the Father" ought to humble every attempt to reduce this mystery to a theological formula.