Catechesis on the Holy Trinity

Bishop Hugh Gilbert OSB Catechesis on the Holy Trinity


I would like to say something about the feast we keep this Sunday, the Solemnity of the Most Holy Trinity.

We have just passed through the whole cycle of Lent and Easter, ending on a high note with Pentecost last Sunday. Now it’s ‘Green Time’, Ordinary Time, again and will be to the end of the liturgical year in late November.

But, as we know, Ordinary Time has its feasts as well, and in the time immediately after Pentecost three. There’s the feast of the Trinity this Sunday, then next Sunday the feast of the Body and Blood of Christ, and then, the Friday after, the feast of the Sacred Heart. Three major feasts in less than two weeks, all solemnities.

They belong together. Liturgy has a history. It has built up over time. The Lent/ Easter cycle developed early. Then came Advent / Christmas. The Trinity, Corpus Christi and the Sacred Heart belong to a later stage. A feast of the Trinity appears from the 9th century, Corpus Christi from the 13th, the Sacred Heart from the 17th. They belong together at another level too. They all presuppose what has gone before, what has been celebrated in the Christmas cycle and especially the Easter cycle. They all look back on it; and they each draw from it one aspect and ask us to focus on it. In the case of the feast of the Trinity, that’s clear. The whole Christmas, Easter, Pentecost story have the Father, Son and Holy Spirit as their source and content; they are the main actors. Then the Eucharist, because Christmas and Easter bring us Jesus and Jesus is wholly present in the Sacrament of his Body and Blood; it sums it all up and enables us to take and eat it. Then the Sacred Heart, because this is a love-story and Jesus’ heart is the symbol and wellspring of his love.

Another comparison. At a concert, the performers return sometimes and give us an encore. It’s as if from Advent to Pentecost we have been listening to a grand concerto. Then we are treated to these three encores. The conductor, the soloist, or whoever comes back on the stage, play something again, and we can applaud and appreciate again. These are feasts of appreciation.

Another comparison. You know the pleasure of skimming stones across water and seeing how many times they bounce. And how if you throw well, you can get a good distance between each bounce on the water. Then the stone does just a few short ones, and sinks. Imagine, each liturgical year, God the Father on the shore of eternity. He throws the smooth stone of his Son into the water of the world. First bounce, Christmas; second bounce, Easter. It’s a good throw, 50 days more, third bounce, Pentecost. And then, yes, it slows down, three short bounces in succession: the Trinity, Corpus Christi and Sacred Heart. Does the stone then sink without trace? I hope not. I think it sinks into our hearts and becomes the foundation stone of a building, of the Temple of God that we are individually and collectively, the Church – but that’s another story.


So, let’s look at this feast.

The Entrance Antiphon goes: “Blest be God the Father, and the only-begotten Son of God, and also the Holy Spirit, for he has shown us his love.”

What we are doing on Trinity Sunday is looking back at the whole story from Advent on. We are, as it were, “reviewing” it. And as we do, we realise that the chief actor is the triune (one in three) God. The Father has sent the Son (Christmas) and, then, through the Son (dying and rising at Easter), the Holy Spirit (Pentecost). These events are the outward signs of God’s inner being; as the theologians say, the missions in time reveal the processions of God’s eternity, his inner life.  God has drawn close to us as Father, Son and Holy Spirit. He has let us into the secret of his being. At the Last Supper, Jesus says, “I call you friends because I have made known to you everything I have heard from my Father” (Jn 12:15). St Thomas Aquinas comments: “the true mark of friendship is that a friend reveals to his friend the inmost secrets of his heart.” This is what God has done. And St Thomas goes on: “Since friends are one in heart and soul, when a friend reveals himself to his friend, he doesn’t go outside himself.” So we can say that when God makes us his friends by disclosing himself, he is inviting us into himself, into his own house, as it were.  Vatican II’s Constitution Dei Verbum, on Divine Revelation, has a shot at summing things up: “It has pleased God in his goodness and wisdom to reveal himself and to make known to us the hidden purpose of his will, by which through Christ, the Word made flesh, man might have access to the Father in the Holy Spirit and come to share in the divine nature. Through this revelation, the unseen God, out of the abundance of his love speaks to humans as his friends and lives among them, so that he might invite and take them into fellowship with himself” (DV2). Another way of telling the same story.

St Irenaeus, an early Christian writer, uses a metaphor – it is only a metaphor – of the Son and the Spirit as the two hands of the Father. Through them the Father has created the universe, the world, human beings and through them he has drawn it back to himself in the process of redemption. Everything flowing from him and back to him, and we embraced.

For some forty years now, a Franciscan priest, Fr Raniero Cantalamessa, has been “preacher to the papal household”. He has preached numerous sermons and published many books. One wee one is called “Contemplating the Trinity”. And what I really like is its subtitle: “the path to an abundant Christian life”.

Emotionally, psychologically, spiritually, this feast is all about abundance. The TRINITY is God’s abundance and as we come to realise and relish the reality of it, so our life can abound.

So, the Entrance Antiphon blesses God the Father, the only-begotten Son and the Holy Spirit “for he has shown us his love.” The Latin says, because he “has done mercy with us”: the great mercy of knowing and loving God as he really is, as he has shown himself to be.

I mentioned in the Catechesis on Pentecost that in the Christian East, Pentecost is the feast of the Trinity. When the Holy Spirit comes, God’s sharing of himself is complete. One of the Fathers says – I paraphrase – “God the Father has been revealed in the Old Testament, the Son of God in the New, and the Holy Spirit in the Church” (that is, from Pentecost on). Now, we stand back and “see”. We should be gasping, feeling “wowed”. This is fullness. There’s a famous antiphon from the Eastern liturgy often quoted here: “We have seen the true light, we have received the Heavenly Spirit, we have found the true faith, and we worship the indivisible Trinity; for the Trinity has saved us.” It’s the same idea as our liturgy.

So the readings give us a sense of God’s goodness to us. In the 1st from Exodus, the Lord passes before Moses and proclaims, “Lord, Lord, a God of tenderness and compassion, slow to anger, rich in kindness and faithfulness”. In the 2nd, St Paul ends his second letter to the Corinthians with a Trinitarian prayer-wish: “the grace of our Lord Jesus, the love of God and the fellowship of the Holy Spirit be with you all”. It’s that sense of embrace again. In the Gospel come Jesus’ words: “God loved the world so much that he gave his only Son, so that everyone who believes in him may not be lost but may have eternal life.” “So much…”

So, a sense is built up of us being gifted, of something rich, full, lavish and all encompassing coming to us, God with us in every dimension: a Father who is above and around us, a Son who is beside us, a Spirit who is within us and between us. A God “From whom is everything, through whom is everything, in whom is everything” (Lauds Antiphon).

Atheism is fashionable in some circles in our Anglo-Saxon world. Richard Dawkins is well-known with his books The God Delusion and now, Outgrowing God, and so forth. We could begin an interesting discussion here. But what I want to say is this: we might answer, No, I’m a theist. Fine. Or to make it clearer, I’m a monotheist. Fine again. But don’t stop there. I think we often do. We stop there in our prayers even, maybe. Who do we pray to? “God” perhaps. Fine. “Jesus”. Fine. But have we grasped that we are not any kind of monotheist? We are Trinitarian monotheists. This feast first emerged in the 8th and 9th cc., and the Christians of that time had a simple, touching phrase for their faith: “the faith of the Holy Trinity / fides sanctae Trinitatis”. St Bede, the great Northumbrian monk and historian, used it often. It evoked all sorts of things for them. It was, in part, a response to early Islam. It captured for them the richness of God’s gift and of the faith by which we open ourselves to it, the joy of believing in the Trinity, in a God who is one and three – without those two realities cancelling each other. What is the Trinity? The Trinity is not an extra, optional app in our Christian life. “I believe in God”. So, I have downloaded the God program into the computer of my life. And then up pops an advertisement, Get the Trinity app. I think, no, I won’t, too complicated. I’ve got God. I’ve got Jesus. But the divine programme is Father, Son and Holy Spirit. The advert’s a scam. God is Trinity. The Trinity’s not an add-on. Nor for that matter, a theological rubic cube: how can three be one? It’s the path to an abundant Christian life.

Let me quote Fr Cantalamessa. “Oh, how wonderful it is to have the Trinity as our God! When we discover the Trinity, we are no longer tempted to exchange Christian monotheism for any other monotheism. I would feel sorry for any God who had no one with whom to communicate and to share his joy with the profundity that is uniquely his. I think he would feel himself tremendously alone and unhappy! The proof of the Trinity’s existence appears on the first page of the Bible: ‘God created man in his own image’, and precisely because we were to be in his image, he added, ‘It is not good for man to be alone’ (Gen 1:27; 2:18).” Yes, there’s a thought. We are individuals because God is one. We are social, we need and want others in our lives, because God is three. It’s not that we have to “explain” the Trinity – the rubic cube. It’s the Trinity that explains us.

“The path to the abundant Christian life.”

And we can say, the path to abundant Christian prayer as well. “Our Father” and we his children. St Therese of Lisieux, saying the Lord’s Prayer, sometimes couldn’t get beyond those words – so beautiful do they seem to her. We are no longer orphans. “Jesus, I trust you”; “Lord Jesus Christ, Son of the living God, have mercy on me a sinner”, “Come, Lord Jesus”: we pray to the Son. We pray through him, with him, in him. We have a brother, a companion. “I will come to you”, he says. “Come, Holy Spirit”, too. Veni, Sancte Spiritus, Veni Creator Spiritus. “He will be with you; he will be in you”, says Jesus (Jn 14:18). “We do not know how to pray as we ought, but the Spirit himself intercedes for us with sighs too deep for words” (Rom 8:26). So, God prays in us. Christian prayer has this Trinitarian abundance to it.

The Father has unveiled his co-eternal Son and sent him among us. The Father and the Son then complete the gift and send us their Spirit. That is, as it were, Advent to Pentecost. “‘I am the Alpha and the Omega’, says the Lord God, who is and who was and who is to come, the Almighty” (Rev 1:8). Yes, the Trinity is the beginning and the end. We begin Mass, “In the name of…”, and end with, “May almighty God bless you…”  Our Christian life begins being baptized in the name of the Father, the Son and the Holy Spirit, and when we are dying, the prayer is said: “Go forth, Christian soul, from this world, in the name of God, the almighty Father, who created you; in the name of Jesus Christ, the Son of the living God, who suffered for you; in the name of the Holy Spirit who was poured out upon you…” We are encompassed.

On Trinity Sunday, we say ‘Yes’ to this abundance. We profess “the faith of the Holy Trinity”, Christian, Trinitarian monotheism. We don’t need to work it all out during the Mass. We are just meant to rejoice in it, gaudium de veritate.

There’s “praise and worship” music, isn’t there? Some like it, some don’t. But, music aside, Trinity Sunday is for “praise and worship”. This is our response to God the Father sending us the Word of truth and the Spirit of holiness. The first word of that Entrance Antiphon is “blest” or “blessed”. “You are blest, Lord God of our Fathers”, says the Responsorial Psalm. “Glory be to the Father and to the Son and to the Holy Spirit”, says the Gospel Acclamation. Both the Mass and the Divine Office for this day pile up words like acknowledge, confess, profess, thank, bless, adore, glorify, praise. This is the first fruit of Pentecost: praise. Praise takes us out of ourselves. Praise comes from love and gratitude. Praise anticipates heaven. The word praise links to our words “prize” and “precious” and “appreciate”. We praise what we prize and appreciate, we praise what is precious. “The faith of the Holy Trinity”. Trinity Sunday is a praise-day: of Trinity in Unity, and Unity in Trinity, “praised by Angels and Archangels, Cherubim too and Seraphim”, says the Preface. “Holy, holy, holy”.


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