Three Persons in One God: More Than Just Doctrine

Trinity 5“Let us make man in our image,” God says in the book of Genesis (1:26), using a curious plural that seems out of place in the scriptures of a monotheistic faith. Indeed every other reference in the early Creation story speaks of God in the singular except this instance. Catholic exegesis has long seen in this grammatical peculiarity an early hint of the doctrine of the Trinity. Though fully revealed only with Christ’s coming, God began uncovering the mysterious nature of his own existence early in his revelation to man. The doctrine of the Trinity is unique to Christianity and serves to set our theology apart, but there’s more to this doctrine than a simple theological assertion to be accepted and then left alone. The Trinity matters.

The Church teaches de fide that the existence of God is knowable by natural human reason. The idea of God developed by Western Greek philosophers on the basis of reason before the advent of Christianity congrues remarkably with aspects of God as found in revelation, such as His omnipotence and omniscience, His unchangeability, his nature as an ultimately simple and absolute Being which is in fact Being Itself.

This philosophy is sound and edifying, yet alone this rational vision of God can be somewhat cold and distant. Greek philosophers, on first hearing the message of Christianity, were scandalized not only by Christ’s ignominious death, but by the very suggestion that such a transcendent God could care for man. Christ’s sacrificial death on the Cross is “a stumbling block to Jews and foolishness to Gentiles” writes Paul, having in mind the (not unrespectable) wisdom of the Greek philosophers (1 Corinthians 1:23). For Christians, it is precisely the revelation of the Trinity that sheds light on the way in which the detached and abstract God we know by reason can also be the dynamic, sacrificing Christian God of love. If God really is a Trinity of love and relationship, his creation of man and desire for a relationship with him becomes more plausible than it would seem solely under the cold calculation of the philosophical picture.

Returning to Genesis, we see that this first hint of the Trinity is made precisely at the moment when God creates man, as the scripture says, in his own image. This clue is very important, because it reveals that God’s Trinitarian nature tells us not only about him, but also about ourselves as well. If God’s existence as a Trinity means that his own nature is in some mysterious sense relational, and we are made in that same image, then relationality is an intrinsic part of our own existence as well.


The first and most fundamental relational aspect of human nature is of course in our own relationship to God. Augustine’s famous cry, “You have made us for Yourself, and our hearts are restless until they rest in You,” captures this fact of our nature: we are incomplete without him. We cannot exist as radically independent beings, we can only really be by having a relationship with our Creator.

This relational aspect also extends beyond the individual relationship to God. In Aristotle’s famous classification, “man is a political animal.” Aristotle meant not that man enjoys parliaments and voting, but that he naturally organizes himself into structured societies with others. The first of all these societies is the family; of all relationships, this one is inescapable. Everyone is born of a mother and father. It should not be a surprise then that nowhere else do we find the Trinity more closely imaged in human nature than in the natural institution of the family.  As the Catechism of the Catholic Church states, “The Christian family is a communion of persons, a sign and image of the communion of the Father and the Son in the Holy Spirit. In the procreation and education of children it reflects the Father’s work of creation” (CCC 2205).

The traditional commentary – we cannot go so far as to say explanation – on the Trinity focuses on God the Father’s self-knowledge being itself a Person, the Son, and on the love between them producing another Person, the Spirit. The language is vague and mysterious, as the nature is finally beyond us. Yet we see the same theme echoed in Adam’s first sight of Eve, recognizing in her “bone of my bone and flesh of my flesh”, capturing a certain loving intimacy and familiarity in the spousal relationship. From this intimacy, of course, comes new life. In the Creed we recite every Sunday, we profess our belief that the Spirit “proceeds from the Father and the Son” and just so does new life proceed from the union of spouses in a family. Around this fundamental and central social relationship of the family, all of the other structures of a society are formed. The nature of God himself is echoed in our human relationships.

Trinity Sunday, the Church’s yearly liturgical recognition of this unique doctrine, falls on May 26th this year. As we celebrate this day, let us remember that our belief in the Trinity is more than a dry and esoteric doctrine. As Genesis reminds us, echoes of the Trinity are part of our own nature as images of God.


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Michael Baruzzini


Michael Baruzzini is a writer on Catholic and science issues, and his writing may be found online at He lives with his wife and children in Virginia."

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