We believe in the Blessed Trinity because we believe in Jesus, Who revealed the Trinity. God had prepared the Jews not only to welcome the Messiah, but to recognize through revelation what philosophers like Aristotle achieved through reason: that there is a God and there can only be one God.
Moses said to the Jews, “Acknowledge today and take to heart that the Lord is God in heaven above and on the earth beneath; there is no other but to believe in God Who is the only God.” When the Messiah finally came, He revealed a huge mystery that went far beyond what the Jews were expecting: that the one God in Whom they believe is not solitary, but a unity, a communion of three persons, Father, Son and Holy Spirit, and that the Messiah is the Son.
He told them explicitly that the Father and He are one (Jn 10:30). He told them that He and the Father would send the Holy Spirit (Jn 14:26, Jn 15:26). And when He sent them out to baptize in the name of God, He didn’t give them instructions to baptize in the “names” of the Father, Son and Holy Spirit — as if they were three different gods — but in the “name,” for they are fundamentally a union of three persons. This is what the term Trinity means. It was devised by the early Church apologist Tertullian around the year 200 from the Latin words “unitas” and “trinus,” literally “unity” and “three.” It signifies that there is a unity of three persons in one God.
Since the beginning of the Church, theologians have spent their lives trying to penetrate this mystery and explain it to others. St. Patrick used the image of a three-leaf clover. St. Augustine used the image of the mind, with memory, reason and will. More recent minds have used the image of H20, which can exist as ice, water, or steam. But none of these analogies — though interesting and somewhat helpful — do justice to the reality of the mystery of how three persons can exist in the one God.
When St. Augustine was in the middle of his voluminous and classic study of the Blessed Trinity, he took a walk along the beach in northern Africa to try to clear his head and pray. He saw a young girl repeatedly filling a scallop shell with sea water and emptying it into a hole she had dug in the sand. “What are you doing?” Augustine tenderly asked. “I'm trying to empty the sea into this hole,” the child replied. “How do you think that with a little shell,” Augustine retorted, “you can possibly empty this immense ocean into a tiny hole?” The little girl countered, “And how do you, with your small head, think you can comprehend the immensity of God?” As soon as the girl said this, she disappeared, convincing Augustine that she had been an angel sent to teach him an important lesson: No matter how gifted God had made him, he would never be able to comprehend fully the mystery of the Trinity.
This, of course, does not mean we cannot understand anything. If we want to get to the heart of the mystery of the Trinity, we can turn to the most theological of the Apostles, who meditated deeply on all that Jesus had revealed and, inspired by the Holy Spirit, said simply and synthetically, “God is love” (1 Jn 4:16). For God to be love, He has to love someone. None of us can love in a vacuum; there must always be an object of our love. Who is the object of God’s love? It cannot be man, or the created world, or the universe, because all of these existed in time and God is eternal and therefore existed before time.
It’s also impossible to say that God merely loved Himself in a solitary way, because this would not really be love but a form of egotism and narcissism. For God to be love, there needed to be an eternal relationship of love, with one who loves, one who is loved, and the love that unites them. This is what exists in the Blessed Trinity: The Father loved His image, the Son, so much that their mutual and eternal love “spirated” or “generated” the Holy Spirit. They exist in a communion of love. The three persons of the Blessed Trinity are united in absolutely everything except, as the early Church councils said, their “relations of origin,” what it means to be Father, what it means to be Son of the Father, and what it means to proceed from the Father and the Son.
These theological insights about the blessed Trinity may seem theoretical, but they become highly practical when we reflect on the fact that we have been made in the image and likeness of God and called to communion with God. To be in the image and likeness of God means to be created in the image and likeness of a communion of persons in love. Our belief in the Trinity — the central teaching of the Catholic faith — has given the Church the deepest understanding available to human beings of the nature of man, the meaning of human life, and what it means to love.
Father Roger J. Landry is a priest of the Diocese of Fall River, Massachusetts, ordained in 1999. After receiving a biology degree from Harvard College, Fr. Landry studied for the priesthood in Maryland, Toronto, and for several years in Rome. He speaks widely on the thought of Pope John Paul II and on apologetics, and is currently parochial administrator of St. Anthony of Padua in New Bedford, MA and Executive Editor of The Anchor, the weekly newspaper of the Diocese of Fall River. An archive of his homilies and articles can be found at catholicpreaching.com.
This article is adapted from one of Father Landry’s recent homilies.
