The Trinity
Catholics worship one God in three distinct Persons: Father, Son, and Holy Spirit. The Persons share one divine nature, so the Son and Spirit are neither creatures nor lesser gods. Catholic teaching receives the Latin Filioque while also distinguishing the eternal procession of the Spirit from the Spirit's mission in history.
Why it matters
Baptism, the creed, prayer, and the liturgy all address the triune God.
Historical context
Nicaea (325) defended the Son's full divinity, and Constantinople (381) confessed the Spirit as Lord and giver of life. The Latin addition to the creed developed later and is disputed by Orthodox churches.
Pastoral note
This introduction supports study; ask a parish or diocesan formation team about preparation and reception in your local church.
Learning objectives
- State the difference between one divine nature and three Persons.
- Locate Trinitarian language in the baptismal formula and creed.
- Identify the Filioque as a later East–West dispute.
Essentials
- The Father, Son, and Holy Spirit are fully divine.
- The Persons are distinct without being three gods.
- Catholic teaching treats the Spirit's procession as a doctrinal question requiring careful terminology.
Common questions
- How can God be one and three?
- What does the Filioque say, and why is it disputed?
Practice and discussion
- Read the Nicene Creed slowly and mark each reference to Father, Son, and Spirit.
- Open the Filioque comparison before describing another church's position.
Scripture
- Matthew 28:19 — Baptism names Father, Son, and Holy Spirit together.
- 2 Corinthians 13:14 — Paul's blessing invokes Christ, God, and the Spirit.
- John 15:26 — The text is central to discussion of the Spirit's procession and mission; later formulas need historical context.
Primary sources
The Nicene creed confesses the Son as:
Nicaea calls the Son consubstantial with the Father.
being of one substance (ὁμοούσιον, consubstantialem) with the Father
Passage context and translation
The council uses the term homoousios to confess the Son's full divinity against Arian claims that the Son is a creature.
Before the excerpt
very God of very God, begotten (γεννηθέντα), not made,
After the excerpt
By whom all things were made, both which be in heaven and in earth.
Augustine writes in On the Trinity:
Augustine describes Father and Son as one beginning of the Spirit rather than two beginnings.
the Father and the Son are a Beginning of the Holy Spirit, not two Beginnings
Passage context and translation
Augustine reasons about the Father's and Son's relation to the Spirit while insisting that the Trinity is not divided into competing sources.
Before the excerpt
it must be admitted that
After the excerpt
but as the Father and Son are one God, and one Creator, and one Lord relatively to the creature