I was recently in conversation with a reader of my blog who asked me how he might go about explaining the Trinity to someone with little background in the subject. I thought I might share some of my own catechetical approach.
First of all, we need to recognize that because the Trinity is a mystery, it is often very hard to say what it is, but easier to say what it isn’t. Explaining the Trinity follows a pattern similar to the approach Michaelangelo had to carving a statue. He used to say that the form of the statue was already in the block of marble — he only removed the useless bits surrounding it. Approaching the Trinity is a bit like that: in ascertaining what the Trinity *isn’t*, we actually are letting the real picture emerge.
Next, we need to recognize that any language we use to describe the Trinity will necessarily be some form of analogy. This leads to the use of images and symbols (think of St. Patrick and the shamrock) to help us grasp the mystery as best we can. In a sense, as much as we using the symbols to “explain” the Trinty, we are also using the symbols to demonstrate that the Trinity, while mysterious, is also intelligible. In other words, just because the Trinity is a mystery doesn’t mean we should shut off our brains. The images and symbols help us to see that there is something about the Trinity that can make sense — it isn’t just a question of Christians not being able to count.
The image I tend to use to communicate this intelligibility of the Trinity is the analogy of a portable CD player. In traditional theology the Father is called the “source” of the Trinity — just as the actual CD unit itself is the “source” for the system. The Son would be represented by the headphones: part of the portable CD player and yet distinct from it, he is the means by which the music that is contained in the CD player is reveals outside of the inner heart of God. And the Holy Spirit? He’s the music itself, flowing from the heart of the unit, through the headphones, into…..us. Or, to put it in theological language, by placing our faith in Christ (putting on the headphones) we are in true union with the Father (the Source) and we receive the Holy Spirit in us (the music in our ears), allowing us to share in the very nature of God.