Foundations of the Faith Part 4: The central mystery of our faith

This is the fourth of a 12-part series that will cover core teachings of the Catholic faith. Once a month from January through December, this space will focus on exploring a specific aspect of the Church’s teaching. To read and share this and the previous parts of the series, visit

Next month’s topic: Membership in the Church

No matter how one puts it, the Christian belief in the Holy Trinity is a difficult teaching to get one’s mind around. The Athanasian Creed, written around the fourth or fifth century, puts it this way: “We worship one God in Trinity and Trinity in Unity, neither confounding the persons nor dividing the substance.”

How can God be one divine substance and at the same time three distinct persons? It’s not one God appearing as Father or Son or Spirit at separate moments. Each one is who he is, and yet there remains one God.

Experience the Trinity

Perhaps one way to approach the mystery of the Trinity is to avoid putting too much emphasis on explanations and more on experience. This is not to suggest a retreat from the rational, but rather to affirm that all human experience — including faith experience — can contribute to our knowledge as well.

The Trinity at Mass
A venerable principle of Catholic teaching is “Lex Orandi, Lex Credendi,” which means that the Church prays what it believes. When the community gathers at Mass, they are not participating in an empty ritual, but in a real communion of love that is celebrated. Priest and people, united in Christ, through the power of the Holy Spirit, offer worship to the Father. Consider the preface to the liturgy of the Eucharist for the Mass of the Most Holy Trinity:

For example, how would you, dear reader, like to have yourself explained? A panel of experts consisting of a physiologist, a psychologist and a spiritual master could be convened to determine once and for all who you are. At the end of a three-year study, the panel could issue an exhaustive report with bar graphs and pie charts and statistics, detailing everything about you down to your biochemical make-up. A news conference would be called and a panel of distinguished experts would announce with absolute certainty: this is John (or Jane); nothing more can be known about him (or her).

The very idea of being able to explain fully an individual human being is, of course, ridiculous. Having a complete list of facts about someone — even if it is possible to compile — does not lead to a complete understanding of the person at his or her depths. At best, such a list provides a “snapshot” of the person at a certain moment in time. Interesting facts? Yes. A full revelation of the human person? No.

The descent of the Holy Spirit at Pentecost. Renata Sedmakova via

The truth is this: Each human being is a mystery who can never be explained fully. And yet, at the same time, each human being can be known in a deep and real way if one is willing to enter into a close relationship with that person.

The same is true for coming to know the Holy Trinity. Human categories of thought and language are ultimately inadequate to express the full mystery of the Trinity. Our knowledge of God as triune — three divine persons — is not the product of investigation but the fruit of revealed truth. The clearest example is what has come to be known as the Great Commission, which Jesus, as the resurrected Lord, spoke to his apostles just prior to ascending to heaven: “Go, therefore, and make disciples of all nations, baptizing them in the name of the Father, and of the Son, and of the holy Spirit, teaching them to observe all that I have commanded you. And behold, I am with you always, until the end of the age” (Mt 29:19-20).

The apostles received the words of Jesus, and his deeds, not as bits of data to analyze, but as the revelation of God to act upon. In doing so, they began to build up the Church that Jesus intended to establish: a community of persons who, through Jesus, may participate in the communion of the Trinity. This experience does not preclude the Church from trying to understand Jesus’ words or from examining them with the lens of theology. But it includes more. The relationship with Jesus, as individuals and as a Church, makes it possible to come to know the Trinity.

Revealed by the Son

Through his incarnation, and eventually through his public ministry, Jesus revealed (by word and deed) not only humanity to itself, but also God to humanity. Indeed, the fact that Jesus would often make declarative statements about God is what brought him into such great disfavor with many of the religious leaders at the time. Nevertheless, many others — having heard Jesus speak and witnessed his amazing signs — believed in him and became his disciples. By yielding to Jesus and being open to his gospel, the disciples were brought to a deeper understanding of the inner life of God, and years later, when the Church was in its beginning stages, they passed on what they had received.

The baptism of Jesus. Zvonimir Atletic via

One of the first things revealed by Jesus concerns God the Father, which may seem odd to anyone familiar with the Jewish faith. Why would Jesus have to reveal the Father to the Jewish people? They were already aware of God as a father and a protector through the preaching of the prophets and through the experience of having been made a nation by God. They took for granted that God the Father had created everything, that he had led Israel to the promised land, and, indeed, that he would always care for them. God the Father was already well known to the Jewish people.

But Jesus reveals something new: God is not only a father to the Jewish people; he is father to Jesus in a unique and exclusive way. Jesus is well known for referring to God as Father, but he also says repeatedly that he was sent by the Father (cf. Jn 8:29; 17:18; 20:21). Moreover, Jesus claims a special relationship: “All things have been handed over to me by my Father. No one knows the Son except the Father, and no one knows the Father except the Son and anyone to whom the Son wishes to reveal him” (Mt 11:27; see also Jn 14:7). Finally, Jesus reveals that the special relationship he enjoys with the Father discloses a previously unknown truth: “The Father and I are one” (cf. Jn 10:30).

If Jesus had said nothing else, then the Church would have had to discern only what he meant by his references to the Father. However, as has already been noted, Jesus tells his disciples to baptize people in the name of the Father and of the Son and of the Holy Spirit. He also reassures his disciples that he will be with them always through “the Spirit of truth” (Jn 14:16-17), the same Spirit who remained with Jesus throughout his ministry (Jn 1:29-35) and who would be given to the Church at Pentecost by both Father and Son. Indeed, the Spirit is the presence of God at work in the Church, leading all the members toward the fulfillment of the divine will which ends in eternal life. The references to the Holy Spirit, therefore, disclose another truth about the inner life of God, namely that God is a unity of three persons. Those who are baptized according to Jesus’ instruction share not only in the gift of the Holy Spirit but also in the Trinitarian communion.

Words for love

When considering the inner life of God, it is important to remember that whatever can be said is the fruit of prayerful discernment on the part of the Church for hundreds of years. Moreover, what has been said is articulated in words that have been used to help explain the mystery of the Trinity. The original disciples would most likely scratch their heads if someone mentioned the word “trinity” to them. Even the word “person” is used in a highly technical sense that is distinguished from its application to human beings. When used of God, “person” is intended to denote the distinctions within the Godhead. Based on Jesus’ ministry and the experience of the apostles, the Church gradually described God in this way: “It is the Father who generates, the Son who is begotten, and the Holy Spirit who proceeds” (CCC, No. 254). The very action of God in human history, revealed as Father, Son and Holy Spirit, also gives us a glimpse of the eternal relations of the Trinity.

Numerous Heresies
In order to protect the teaching of the Trinity that it had received from Sacred Tradition and Sacred Scripture, the Church had to defeat a number of heresies during the first few centuries following the life of Christ.

While the present age has benefitted from the prayer and thought of the Church in years past when it comes to appreciation of the Trinity, no time period has ever been without the eternal witness of Jesus, whose words and deeds remain potent and active in the lives of his disciples.

Jesus did not use technical theological language, but rather stories and parables that expressed the truth in a more immediate way. When he spoke about the Father and Spirit, he always used relational terms that underscored the essential Trinitarian truth: God is love. Indeed, it finally dawns upon the Church as it discerned the gospel that the essential meaning of the Trinity is an outpouring of love that gives birth to creation and that extends the offer of eternal life to all mankind.

The belief in the Holy Trinity did not come about through abstract thought or the collection of data, even though the Church did develop eventually a formal doctrine. The Trinity was revealed long before it was part of a catechism. As the members of the Church made the effort to receive well the gospel of Christ, and to love each other, they began to experience on a deep level the union Jesus promised, which bore fruit in the spreading of the faith and the sharing of life with God.

“To believe in the Trinity is to believe that there is only one God, and that there are three distinct Persons who possess eternally the same divine nature. To say that there is only one God or only one divine nature is to say that there is no plurality of divine beings. Thus there is only one Wisdom, one Love, one Life that is God, the source and goal of all. The one only God exists in three Persons, the Father, the Son, and the Holy Spirit, three who are distinct, but who know us with one infinite wisdom and who love us with one eternal love, and with whom we can enter into personal relationships through grace.”

One of those fruits is how the truth of the Trinity is reflected in the human family. “The word of God tells us that the family is entrusted to a man, a woman and their children, so that they may become a communion of persons in the image of the union of the Father, the Son and the Holy Spirit. Begetting and raising children, for its part, mirrors God’s creative work” (Amoris Laetitia, No. 29). Just as the communion of Father, Son and Spirit give life, the family is called to do so as well. And not just in the obvious way of having children, as grand a blessing as this may be. The family also gives life when they work together, enjoy each other’s company, forgive, pray and even play together. Moreover, a family is able to reflect God’s love when it contributes to the common good through charitable service. In short, the family mirrors the Trinity best when it truly lives in the Spirit of Christ.

The best way for anyone to come to a knowledge of the reality of the Holy Trinity is to act upon the words and deeds of Christ: “Whoever loves me will keep my word, and my Father will love him, and we will come to him and make our dwelling with him. ... The Advocate, the holy Spirit that the Father will send in my name — he will teach you everything and remind you of all that [I] told you” (Jn 14:23, 26).

Baptism in the name of the Trinity is central to our identity as Christians. Angelo Giampiccolo via

Living this truth

As an institution, the Church has never ceased to live its Trinitarian faith. Every new Christian is initiated through baptism, the prayers of which call upon the Trinity to free the newly baptized from sin and to bring him or her into the communion with the head, Jesus, and his members, the people of God.

Every celebration of the Eucharist, moreover, begins and ends with the Sign of the Cross, which signifies the assembly’s participation in the life of the Trinity.

Metaphors fail
There have been many attempts to try to explain the Trinity, the most famous attributed to St. Patrick. Evidently, St. Patrick tried to show how a shamrock, which is a single plant with three leaves, is analogous to the one triune God with three distinct persons. Others have used water, which is always H2O but can be a liquid, ice or steam. Still others speak about one woman being at the same time mother, daughter and sister. Ultimately, each example falls short of the Church’s belief in the Trinity because, while each shows how something can have “oneness” and “threeness” at the same time, none of them capture the truth of the Trinity. For God is not made up of parts, and he does not exist in different modes or forms. He is Father, Son and Spirit: three distinct persons, but one divine substance.

To return to the initial example of coming to know a fellow human being: we do so by spending time with the person, by talking and listening and sharing experiences with them. The person is known more or less deeply depending on the quantity and quality of time shared. Our faith tells us that God wants to be known in a similar way, which is why Jesus is the Incarnate Son.

As a human being, Jesus can be known by us; we can enter into a relationship with him. We can read his words, meditate on his deeds, imitate his life and speak to him through our prayers.

“[The] confession of the triune God is a deep mystery that no created spirit can discover of itself or ever comprehend. It is the mystery of an unfathomable and overflowing love: God is not a solitary being, but a God who bestows and communicates himself out of the abundance of his being, a God who lives in the communion of Father, Son, and Spirit, and who can therefore also bestow and ground community. Because he is life and love in himself, God is able to be life and love for us. We are included from all eternity in the mystery of God. From all eternity God has a place for us. The confession of the triune God is ultimately an exposition of the single sentence “God is love” (1 Jn 4:8, 16b). God in himself is life and love from all eternity, so that he grounds hope for us in the midst of a world of death and hate. We should know in faith that the ultimate and deepest reality is life and love and that a share in this reality is bestowed on us through Jesus Christ in the Holy Spirit.”

And as a divine person, Jesus can unite us to himself so that we partake in the communion of love, which bears the fruit of peace and trust, giving us the grace to anticipate the life of heaven even now.

So, while it may be true that no one can fully explain the Trinity, it is possible to invite others to experience the Trinity through the way one participates in the love of Father, Son and Spirit.

David Werning writes from Virginia.

Nihil Obstat: Msgr. Michael Heintz, Censor Librorum