The Living Tradition An Orthodox Archive of the Church Fathers and Early Church

Theme

The Holy Trinity

One God in three persons: how the Church came to say it, and why the words were fought over.

  • Dogmatic definitionDefined by an ecumenical council or otherwise confessed by the Church as binding doctrine. Not every sentence a council wrote is a definition: its acts, letters and disciplinary canons are different things.
  • Received Orthodox teachingTaught consistently and received throughout the Orthodox Church, though not necessarily formulated in a conciliar definition. This is not a claim that no Father ever wrote differently.

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Christians pray to the Father, through the Son, in the Holy Spirit, and are baptised into the one name of all three. The doctrine of the Trinity is the Church's attempt to say what that practice commits it to, in language that will not collapse into either three gods or one God wearing three masks.

The settled formula is one ousia in three hypostasis. It took most of the fourth century to arrive at, partly because the two words had been used as synonyms and had to be distinguished before the formula could mean anything. Nicaea in 325 confessed the Son homoousios with the Father; Constantinople in 381 confessed the Spirit as Lord and Giver of life, worshipped and glorified with the Father and the Son.

Orthodox theology insists that this is not a description of God's inner mechanics. The divine ousia is unknowable. What the formula does is mark out how the Church may speak, so that it does not say less than it means at prayer.

Follow this theme through the archive

  • The First Council of Nicaea

    The council that confessed the Son to be of one substance with the Father, addressed the date of Pascha, and issued twenty disciplinary canons. It did not decide which books belong to the Bible.

    Council

  • The First Council of Constantinople

    The council that confessed the divinity of the Holy Spirit and gave the Church the Creed it recites today. It was not ecumenical when it met; the Church made it so by receiving it.

    Council

  • Basil the Great

    Bishop of Caesarea in Cappadocia, organiser of monastic life and of the Church's care for the poor, and the theologian whose work on the Holy Spirit made the Council of Constantinople possible.

    Father or writer

  • Gregory the Theologian

    One of only three figures the Orthodox Church calls the Theologian, whose five orations on the Trinity settled how the Church would speak of God, and who resigned the see of Constantinople rather than prolong a quarrel.

    Father or writer

  • The Creed and the Holy Trinity

    What the Church confesses about God, where the words came from, and why they were fought over.

    Lesson

Sources for this page

  1. Tier C The Seven Ecumenical Councils of the Undivided Church Henry R. Percival (ed.); Philip Schaff and Henry Wace (series eds.) The Seven Ecumenical Councils annotated edition of conciliar texts Source record

Tiers are explained in the methodology. No page on this site has been reviewed or approved by any bishop, priest, synod or seminary.