At the beginning of his papacy, one of the very first things Pope Benedict wanted to recall to the attention of the Bishops, priests, deacons, religious, and lay faithful was the following: “Being Christian is not the result of an ethical choice or a lofty idea, but the encounter with an event, a person, which gives life a new horizon and a decisive direction” (Deus Caritas Est, 1).
What is it that makes a relationship with Jesus different from a relationship with any other human being? The answer has to do with the grace of God. How we habitually think about grace, therefore, affects everything in and about the Christian life.
Let us look at how the Catechism speaks about grace: “Grace is a participation in the life of God. It introduces us into the intimacy of the Trinitarian life” (CCC, 1997). This naturally raises the question of what exactly “participation” means when used in a theological context.
When St. Thomas Aquinas speaks of participation in the Summa Theologiae, he uses a very concrete example. He says, “That which has fire, but is not itself fire, is on fire by participation.” This gives us a very useful mental picture. It is only a picture, of course, but St. Thomas thinks that pictures are helpful for learning, even for people who are good at abstract thought, because that which we know abstractly must be abstracted from something concrete.
Imagine, if you will, a bar of iron being placed in a large, hot fire. The metal, originally dark in color and cool, takes on the qualities of the fire until it becomes fiery. It looks like fire: it becomes red-hot and glows as though it were itself a flame. The fieriness does not merely coat the exterior of the metal but goes all through it to its very center. It not only looks like fire, but also affects things in the way that fire does. If you took that fiery metal and touched it to something, it would burn it.
Yet, although the fire has caused a dramatic change in the metal, it has not taken away its identity as the kind of metal it is or as the individual piece of metal it is. In becoming fiery, the metal has not been destroyed and replaced with a flame, but has taken on new perfections it never could have had without participating in fire. In fact, you could say that the metal has become even more itself, because whatever corruption it had—rust, impurity, dross—gets burned away by the fire until only the good, clean metal remains.
Of course, this is only a picture of our participation in the life of God by grace, not an exact reproduction. Even the best of such pictures break down when they are pushed too hard or too far, because nothing can represent God adequately or exhaustively. For instance, even though Jesus says, “I am the vine, you are the branches,” we can’t mine every detail of viticulture in the hopes of obtaining accurate information about our relationship to Jesus. Nevertheless, there is a reason that God is so often compared to fire, both in the Scriptures and by the saints.
Using our similitude of metal participating in fire, we can see why the Catechism calls sanctifying grace “deifying grace” (CCC, 1999). It is evident that, just as metal cannot become fiery on its own, apart from contact with fire, so our participation in grace must come from God’s initiative rather than from our own natural powers. We can also see how grace does not do away with nature but perfects it: penetrating to the very essence of the soul, it restores it to purity and confers on it additional perfections that transcend its nature.
We have only to look at the lives of the saints to see how the power of grace makes things happen and changes lives. But we should also reflect on how sanctifying grace in this life is only the first beginning of that which comes to its full flowering in the saints in glory.