By loving my wife and being loved by her I learned that a perfect love would make us one. Our love made us more alike. The longer my wife and I spent together the more we became alike. We borrowed each others expressions, gestures and even habits. The more our minds became consumed with how to make one another happy the clearer it became that satisfying the other, not ourselves, gave us our greatest joy. Yet at the same time, as we became more alike and more self-giving, we also became more ourselves. My wife’s love and acceptance gave me the confidence to show her my truest self and she gave me the same honour. It was then that the truth of the Holy Trinity became alive in my heart and my mind: If I loved my wife perfectly I would become perfectly like her and yet this process of being identical would also give me my own true and distinct identity.
Humans are imperfect so we cannot love perfectly but God is Love itself so He can. We are the image of God (Genesis 1:26) and as creatures we reflect our Creator in how we love. Yet, the image is merely a reflection and like a reflection we are only because God Is. In humans existing and doing are not the same e.g. my existing is different to my loving my wife. This fact means I can grow and I can change, I can always go from potentially being something to actually being something. God however reveals himself to Moses as ‘I AM’ (Exodus 3:14), Being itself. St Thomas Aquinas calls God a ‘perfect act’ (ST 1, Q.2, Art.3) because God does not change from potentially being something to actually being something. God’s act of being is so perfect that it leaves no room for becoming something else. God is ‘the Father of lights with whom there is no variation or shadow due to change’ (James 1:17). God cannot be ‘better’, God is ‘Best’. Indeed what we know as goodness, truth and beauty and so on even to their Nth degree are merely creations that reflect the Creator. When we use terms like this of God we are speaking analogously and saying what we understand these things to be is the closest we can get to knowing what God is (ST 1, Q.13, Art.5). In truth to call God Being means we have to refer to ourselves as becoming and if we refer to ourselves as being we must refer to God as ‘Beyond Being’ (DN 1, 1, 588A). To say we are loving means God is Love, to say we love makes God beyond love.
It is because God is so incomprehensibly perfect in love that He can be three persons yet one God. As the image of God we know by analogy through experience that love draws us into relationships. If our love leads to self-realisation through becoming more and more defined by the one we love we can see that God as Love must be constituted by a relationship: The perfection of the Trinity is that persons are entirely and perfectly defined by their relations to one another. This is because that is what it means to love in its truest sense and God is Love. Further, as what it means to love is to be in a relationship and God is by his nature the surpassing perfection of everything God must also by his nature be a relationship and exist as a relationship (ST 1, Q.2, Art.1-4). The persons do not start out separated as we do. God being a perfect act from all eternity exists as Love’s template in perfect self-giving relationship with the Trinity in an infinite embrace. Always three, always one. Father, Son and Holy Spirit. The Lover, the Loved and the Love between them (De Trinitate VIII, 10).