Saints LightWho Is God? The Trinity
There is one God who is Father, Son and Holy Spirit: three Persons, one divine nature. God is a communion of love, and He made us to share it.
Israel's great prayer begins: Hear, O Israel, the Lord our God is one Lord. Christians have never taken that back. There is one God, not three. Yet Jesus revealed something no one could have guessed: the one God is Father, Son and Holy Spirit. This is the Trinity, one God in three divine Persons.
Each Person is fully God, not a third of God. The Father is God, the Son is God, the Holy Spirit is God, and still there is only one God, because the three share one and the same divine nature (CCC 253). At the same time they are really distinct from one another. The Father is not the Son, and the Son is not the Spirit (CCC 254). They are distinguished only by how they relate to each other: the Father begets, the Son is begotten, the Spirit proceeds (CCC 255).
Two common mistakes help show what the Church means. One is to imagine three gods working as a team. The other is to imagine one God wearing three masks, acting first as Father, then as Son, then as Spirit. Both are wrong. God is one, but not solitary.
How do we know this? Not by reasoning it out. The Trinity is a mystery in the strict sense: something we could never know unless God told us (CCC 237). Jesus spoke of His Father, called Himself the Son, and promised to send the Spirit. Then He told the apostles to baptize in the name (singular) of the Father, and of the Son, and of the Holy Spirit. The early councils, Nicaea in 325 and Constantinople in 381, defended this faith in clear words (CCC 242, 245).
Why does it matter? Because St John says God is love, and love needs someone to love. From all eternity God is a communion of self-giving love. He did not create us because He was lonely. He created us to draw us into the love He already is. The Church calls the Trinity the central mystery of Christian faith and life (CCC 234, 261).
Every image falls short, whether a shamrock or water as ice, liquid and steam, and the water image actually suggests the masks mistake. It is better to start where the Church starts: with prayer. Every time you make the Sign of the Cross, you profess the Trinity.
Key points
- There is one God in three divine Persons: Father, Son and Holy Spirit.
- Each Person is fully God, and the three are really distinct, not masks or parts.
- We know the Trinity only because Jesus revealed it; it is a mystery in the strict sense.
- God is an eternal communion of love, and He made us to share in it.
The Word of God
Hear, O Israel, the Lord our God is one Lord.
Going therefore, teach ye all nations; baptizing them in the name of the Father, and of the Son, and of the Holy Ghost.
He that loveth not, knoweth not God: for God is charity.
Catechism paragraphs for this lesson
- CCC 232-237
- CCC 242-245
- CCC 253-256
- CCC 261
CCC means the Catechism of the Catholic Church. Saints Light teaches it in its own words and never quotes it. Look up any paragraph in a printed copy or at vatican.va. See every lesson by paragraph in the Catechism index.
From the tradition
Q. What is the Blessed Trinity? A. The Blessed Trinity is one God in three Divine Persons. Q. Are the three Divine Persons one and the same God? A. The three Divine Persons are one and the same God, having one and the same Divine nature.
Live it this week
Make the Sign of the Cross slowly each morning and night this week, and while you do it, say in your heart: Father, I belong to You. Jesus, I belong to You. Holy Spirit, I belong to You.
Check yourself: three questions
1. Which statement matches Catholic teaching on the Trinity?
- There are three gods who agree perfectly
- One God shows up in three different roles at different times
- The Father is God, while the Son and Spirit are lesser beings
- One God in three really distinct Persons sharing one nature
Show the answer
One God in three really distinct Persons sharing one nature. The three Persons are really distinct yet share one divine nature, so there is one God (CCC 253-254).
2. How do we come to know that God is a Trinity?
- Only because God revealed it, above all through Jesus
- By careful philosophical reasoning alone
- From studying the natural world closely
- Through a feeling each person has in prayer
Show the answer
Only because God revealed it, above all through Jesus. The Trinity is a mystery in the strict sense, which we could not know unless God revealed it (CCC 237).
3. Why is the image of water as ice, liquid and steam a weak picture of the Trinity?
- Because water is too ordinary to stand for God
- Because it suggests one being changing forms, like wearing masks
- Because the Bible forbids comparing God to anything
- Because it implies there are four Persons in God
Show the answer
Because it suggests one being changing forms, like wearing masks. The lesson notes that the water image suggests one God taking turns in three forms, which is the masks mistake.
Words to know
- Trinity
- One God in three divine Persons: Father, Son and Holy Spirit.
- Person (in God)
- Father, Son or Spirit, each fully God, distinguished only by their relation to one another.
More terms in the Catholic glossary. More passages in the Scripture index.
For catechists: a one hour class plan
Goal. The group should understand that there is one God in three divine Persons, and take to heart that God is an eternal communion of love who made us to share in it.
Opener. Ask: "When was the first time you remember someone teaching you the Sign of the Cross, or seeing someone make it?" Let a few people share. Point out that every Sign of the Cross is a short creed in the Trinity.
Discussion questions
- Christians say God is one, yet Father, Son and Holy Spirit. How would you explain that is not three gods? [One divine nature, three really distinct Persons. Gently correct the common mistakes: three gods, or one God wearing three masks.]
- The lesson says we know the Trinity only because Jesus revealed it. Why does that matter? [It is a mystery in the strict sense, not a puzzle we solved. That should make us humble and grateful, not anxious about understanding it fully.]
- What changes if God is a communion of love rather than a lonely power? [Love is not something God does once; it is who He is (1 John 4:8). We were made for relationship because God is relationship.]
- Which Person of the Trinity do you find easiest to pray to, and which feels most distant? [There is no wrong answer. Encourage people to get to know the Person they feel least close to.]
Activity. Teach and practice a slow Sign of the Cross as a group. Then give each person a card and 8 minutes to write three short lines of prayer, one to the Father, one to the Son, one to the Holy Spirit, in their own words. Invite (do not require) two or three volunteers to read theirs aloud.
Closing prayer. Glory to You, Father, who made us. Glory to You, Jesus, who saved us. Glory to You, Holy Spirit, who lives in us. One God, help us belong to You more each day, and teach us to love as You love. Amen.
Timing. Opening prayer 5 min, opener 5 min, read the lesson together 15 min, discussion 20 min, activity 12 min, closing 3 min.
Related lessons
- What Did the Great Councils Settle? (Church History)
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