Council of Chalcedon

What Was the Council of Chalcedon?

The Council of Chalcedon was the Fourth Ecumenical Council of the Catholic Church.

It was held in AD 451 at Chalcedon, a city in Bithynia in Asia Minor.

Its main purpose was to defend the Catholic faith against the errors of Eutyches and the Monophysites.

The Problem After Ephesus

The Council of Ephesus had condemned Nestorius, who divided Christ too sharply as though He were two persons.

Soon after, the opposite error appeared.

Some began teaching that Christ had only one nature after the Incarnation, as though His humanity had been absorbed into His divinity.

What Was Monophysitism?

Monophysitism comes from words meaning “one nature.”

It taught that after the Incarnation there was only one nature in Christ.

The Church rejected this because Jesus Christ is truly God and truly man.

Who Was Eutyches?

Eutyches was a monk near Constantinople who taught that Christ’s humanity was not of the same nature as ours.

He claimed that before the Incarnation there were two natures, but after the union there was only one nature in Christ.

This teaching undermined the truth of Christ’s real humanity.

The Robber Council of Ephesus

In AD 449, a council was held at Ephesus that wrongly supported Eutyches and acted violently against defenders of Catholic doctrine.

Pope Leo I rejected this assembly and called it the Latrocinium, or “Robber Council.”

Chalcedon corrected the errors and injustices of that false council.

Pope Leo the Great and the Tome

Pope Leo I wrote a famous dogmatic letter known as the Tome of Leo.

In it, he explained that Christ is one Person with two natures, divine and human.

Each nature remains complete and acts according to what belongs to it, without destroying the unity of Christ.

The Council Begins

The council opened on October 8, AD 451.

Hundreds of bishops attended, making it one of the largest councils of the early Church.

The papal legates presided in the name of Pope Leo I.

The Faith of Chalcedon

Chalcedon taught that Jesus Christ is one and the same Son, Lord, and Only-begotten.

He is known in two natures:

• Divine nature.
• Human nature.

These two natures are united in one Person.

Without Confusion, Change, Division, or Separation

Chalcedon used four important phrases to protect the truth about Christ.

Without Confusion

Christ’s divinity and humanity are not mixed together into something else.

Without Change

The divine nature does not become human, and the human nature does not become divine.

Without Division

Jesus is not split into two persons.

Without Separation

His divine and human natures are forever united in the one Person of the Son.

Why Christ’s Humanity Matters

If Jesus were not truly human, He could not truly represent us.

He suffered, died, and rose in a real human nature.

Because He is truly man, He can redeem humanity.

Why Christ’s Divinity Matters

If Jesus were not truly God, His saving work would not have infinite power.

Because He is truly God, His sacrifice saves.

Chalcedon protects both truths: Jesus is fully God and fully man.

Dioscurus of Alexandria

Dioscurus, Patriarch of Alexandria, had supported Eutyches and played a major role in the Robber Council of Ephesus.

At Chalcedon, he was judged and deposed.

The council rejected his actions and defended the Catholic doctrine of Christ.

Canon 28 and Rome

Chalcedon also issued disciplinary canons.

One controversial canon attempted to give Constantinople special rank after Rome because it was the imperial city.

Pope Leo rejected this canon, insisting that Rome’s authority rests on succession from Saint Peter, not merely political importance.

Why Chalcedon Matters

Chalcedon gave the Church one of the clearest statements about who Jesus Christ is.

It rejected both the division of Christ and the confusion of His natures.

It remains foundational for Catholic teaching on the Incarnation.

Common Misunderstandings

Jesus Is Not Half God and Half Man

He is fully God and fully man.

Jesus Is Not Two Persons

He is one Divine Person.

Christ’s Humanity Was Not Absorbed

His human nature remains real and complete.

Chalcedon Did Not Invent Christology

It clarified the apostolic faith against serious errors.

Key Truths About Chalcedon

• Chalcedon was held in AD 451.
• It is the Fourth Ecumenical Council.
• It responded to Eutyches and Monophysitism.
• It rejected the Robber Council of Ephesus.
• It affirmed Pope Leo’s teaching on Christ.
• It taught that Christ is one Person in two natures.
• Christ is fully God and fully man.
• His two natures are united without confusion, change, division, or separation.

What Does This Mean For Me?

Chalcedon helps us understand the mystery of Jesus Christ more clearly.

The Savior who died for us is truly man, sharing our humanity.

The Savior who conquers sin and death is truly God.

Because Jesus is one Divine Person in two natures, He is the perfect mediator between God and man.

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Learn how the Church responded to the Protestant Reformation and clarified Catholic doctrine.