What do Catholics mean when they say God is a Trinity?
The mystery of the Holy Trinity is the central mystery of Christian faith and life. Catholics believe that there is only one God, who exists eternally as three distinct divine Persons: the Father, the Son, and the Holy Spirit.
These three Persons are not three separate gods, nor are they merely three masks or roles that one God wears. Each Person is truly and entirely God, sharing the single divine substance and nature. Yet the Father is not the Son, the Son is not the Father, and the Holy Spirit is neither the Father nor the Son.
This truth does not come from human philosophy; Jesus Christ revealed it to us. At its heart, the doctrine reveals that God is not solitary. Within his own eternal being, God is an infinite communion of love, into which he invites every human person to share.
Sources
- Catechism of the Catholic Church, paragraph 253
- Matthew 28:19
- 2 Corinthians 13:14
Awaiting review by the chaplaincy. Written in our own words; the Church's own texts are the authority.