This Sunday is Trinity Sunday. Do you know what’s a good analogy for the Trinity? Nothing. God is so far beyond our ability to comprehend Him, much less to express His inner nature in human speech, that all of our attempts to do so fall miserably short.
Worse, we can get too comfortable with our analogies and images, and think that we’ve finally captured Him. It’s a subtle form of idolatry: instead of a golden calf, we’ve caught Him in a neat analogy or mental image. The history of the Church is filled with Trinitarian heresies, because the Trinity is easier to misunderstand that it is to understand.
That’s not to say that analogies and mental images can’t help, because while we can’t comprehend God, we know something about Him, because He has chosen to reveal Himself to us. When we say that God is Three Persons in One Substance, we don’t understand that Mystery fully, but we’re not just saying meaningless nonsense, either.
And it’s important that we strive to understand what we can about the Trinity. Why? Because we’re talking about the inner life of God. Our whole reason for existing is to know, love, and serve God in this world, so that we can be happy with Him in Heaven. And God has revealed Himself to us precisely so that we can know Him, even though we can never fully comprehend Him.
Here are the pieces of the puzzle that God gives us. Scripture reveals:
- that God the Father is God;
- that God the Son, Jesus Christ, is God;
- that the Holy Spirit is God;
- that these Three are Three distinct Persons; and yet that they are not three separate Gods.
- There is only one God, Father, Son, and Holy Spirit.
- But the Father, Son, and Holy Spirit are each fully God: it’s not as if they’re each 1/3rd of God.
Theologians throughout history have tried to put these pieces together, but it’s not easy. Here are a few keys to help.
First, the Trinity consists of Three Persons in One Substance. That’s the same as saying Three Persons sharing One Nature. So what’s the difference between a “Person” and a “Nature”? Basically, a person is who you are, and a nature is what you are. There’s much more that can be said on this point, but that’s the basic reality. There are Three “Who’s” in the Trinity, but only One “What.”
Second, don’t use overly physical imagery to understand God. If I give you my car, I don’t have my car anymore. But if I share my idea with you, you gain something without me losing anything. Scripture speaks of Christ as the Word of God, and we should take that seriously: God the Father eternally speaks the Word, and He “breathes out” the Holy Spirit through the Son, but He doesn’t lose any of His divinity. That’s how we can speak of each Person being fully God without needing to divide divinity into thirds.
Third, remember that God is love. Love is always bigger than one person: it’s giving yourself to another. And God does this perfectly: the Father pours out His love in begetting the Son, giving the Son everything that the Father has. Jesus says as much in this Sunday’s Gospel: “Everything that the Father has is mine.” He lovingly receives the Father’s substance without the Father loses His substance. And the fruit of this love between the Father and the Son is the Holy Spirit.
It’s this love that overflows for us and it’s this love that saves us upon the Cross. The Fourth Lateran Council explains that the Three Persons of the Trinity share both “a unity of identity in nature,” and “a union of love in grace.” We don’t share the nature of Father, Son, and Holy Spirit: we are not God. But radically, we are invited to share in the union of love in grace, to let the Trinity live in our hearts, to participate in the life of God. That’s not just flowery language: that’s what the Christian life is all about.
Trinity Sunday celebrates a Mystery hard to understand, and impossible to fully comprehend, but the central reality of our faith nevertheless. It’s a reminder that God is love, Lover and Beloved, and that He invites us to participate in this eternal life of love.