Christian History · Timeline

The Age of the Councils

From the Edict of Milan to the Second Council of Nicaea in 787, the newly free church did the hard work of putting its faith into careful words. In a series of worldwide councils, Nicaea, Constantinople, Ephesus, and Chalcedon chief among them, it confessed that Jesus is fully God and fully man, one person in two natures. These centuries also saw the Bible’s canon confirmed and the gospel carried to Ireland, England, Ethiopia, and China.

Once persecution eased, an older question grew urgent: exactly who is Jesus? The councils were not adding to the gospel but guarding it, finding language to hold together what Scripture says, that Jesus is truly divine and truly human, without collapsing into error on either side. The creeds we still recite were forged here.

These same years gave the church much else besides. Athanasius listed the twenty-seven books of the New Testament in 367, Jerome translated the Latin Vulgate, Augustine wrote the Confessions, and missionaries reached the edges of the known world, all the way to Tang China by 635.

The timeline

• AD 325
  The First Council of Nicaea
  The first worldwide council confesses the Son as ‘of one substance’ with the Father and rejects Arianism. It defended, and did not invent, the church’s belief in Christ’s deity.
• c. AD 330
  The conversion of Ethiopia
  Through Frumentius, King Ezana of Aksum embraces Christianity, beginning one of the world’s oldest unbroken Christian traditions.
• AD 367
  Athanasius lists the 27 New Testament books
  In his Easter letter Athanasius names exactly the twenty-seven books Christians still receive as the New Testament.
• AD 381
  The First Council of Constantinople
  The council confesses the full deity of the Holy Spirit and completes what we now call the Nicene Creed.
• AD 382 to 405
  Jerome completes the Latin Vulgate
  Jerome’s translation becomes the Bible of the Western church for the next thousand years.
• AD 397
  The Council of Carthage affirms the canon
  A regional council lists the biblical books the churches had long used, confirming the shape of the New Testament.
• AD 354 to 430
  Augustine of Hippo
  The North African bishop writes the Confessions and The City of God, shaping Western theology for a millennium.
• AD 431
  The Council of Ephesus
  The council affirms that Christ is one person, and that Mary bore the one who is truly God (Theotokos), against Nestorius.
• c. AD 432
  Patrick’s mission to Ireland
  A former slave returns to evangelize the people who once enslaved him, and Ireland becomes Christian.
• AD 451
  The Council of Chalcedon
  Christ is confessed as one person in two natures, fully God and fully man. Over its wording, the Oriental Orthodox churches part from the rest.
• AD 476
  The fall of the Western Roman Empire
  As Rome collapses, the church becomes the great preserver of faith, learning, and order across the West.
• c. AD 529
  Benedict founds Monte Cassino
  His Rule shapes Western monasticism. For centuries, monasteries will copy Scripture and keep learning alive.
• AD 597
  Augustine of Canterbury’s mission to England
  Sent by Pope Gregory the Great, he brings the Roman mission to the Anglo-Saxons.
• AD 635
  The gospel reaches China
  The Church of the East sends Alopen to the Tang capital. The famous Xi’an stele records this early Christian mission along the Silk Road.
• AD 787
  The Second Council of Nicaea
  The seventh ecumenical council settles the use of icons, closing the age of the great early councils.

The thread through it all

Read the whole story and one thing becomes plain: through every century, every council and controversy, every rise and fall of empires, one Person holds it together. The church has been divided, persecuted, corrupted, and renewed, and yet it has never once disappeared, because it was never finally ours to keep. Jesus said he would build it, and he has.

Frequently asked questions

What were the great ecumenical councils?

The first four were Nicaea (325), Constantinople (381), Ephesus (431), and Chalcedon (451). Together they confessed Jesus as fully God and fully man, one person in two natures. The Orthodox and Catholic churches count seven early councils, ending with the Second Council of Nicaea in 787.

What did the Council of Chalcedon decide?

Chalcedon (451) confessed that Jesus Christ is one person in two natures, fully God and fully man, united without confusion, change, division, or separation. It remains the classic statement of orthodox belief about Christ.

When was the New Testament canon settled?

The core books were recognized very early. Athanasius listed the exact twenty-seven New Testament books in 367, and regional councils such as Carthage (397) confirmed the list the churches had long used.