When we predicate “life” of God, we do it analogically. That doesn’t just mean “metaphor.” It has a more precise philosophical function here.
We might say that “life” is a perfection in certain creatures – plants, animals, humans, angels, and whatever else I don’t know about. The perfections found in certain creatures – that they are good, or beautiful, or living – do in fact exist in God. However, they exist in God in a radically different way, that places God in none of those categories. God is not any kind of thing. He is not “a living thing.” He not even “a being.” Rather, living things and beings find their origin in him.
But how is this possible? How is it that we can say “God is good” without God being in the category of good things? When we say “God is good,” we mean it in a very qualified sense: analogically. In short, it runs like this: God is uncomposed of parts. The perfections we find in creatures exist in God. The perfections we find creatures are parts. Therefore, the perfections we find in creatures exist in God in an uncomposed manner (not as parts). That is, a perfection such as “life” exists in God while existing in a manner only infinitesimally like the way it does in creatures (which is as a part of it). It was famously concluded in Lateran Council IV:
“…between Creator and creature no similitude can be expressed without implying an even greater dissimilitude”
DS 806 and
CCC
Obviously, there’s some skips in my own presentation, but that’s the answer minus the scratch work. It essentially means we can’t predicate “life” univocally of God and creatures. We have to predicate it of God as of something uncomposed, and it’s not possible to see that kind of phenomenon in creatures. We find the same answer in St. Thomas:
S.T. Ia Q.13 A.2.
How do we get to that?
All creatures are composed of parts. Even a theoretically un-splittable fundamental particle(s), if there is such a thing(s), is composed of parts. The parts of a creature which are always there, then, are obviously not necessarily physical parts. They are metaphysical: essence and existence. For any necessary clarification, an essence of something is roughly the “whatness” or “quiddity” of something, while the existence of something is the “
that it exists” part. Any creature that does not have its existence as its essence would be identical with God, and therefore actually would be God, and therefore would not be a creature. So, in creatures, their (our) “whatness” is distinct from their actually existing. “What they are” does not mandate “that they exist.” At the risk of being side-tracked here, I would additionally mention that all this holds even if there were, say, an infinitely long sequence of causes in the past. I do not find that contradictory, nor did St. Thomas. I just want to allay any potential objections here.
Creatures other than fundamental particles have additional complexity in their essence (although one could, I suppose, try and make fundamental particles subject to some of
Aristotle’s nine categories other than substance; I’m no scientist, so don’t look at me for that). Some of these creatures that are not fundamental particles have the additional complexity of “life.” No, this has nothing to do with Paley-style ID arguments of which I
and most Thomists are not a fan. All it means is that “life” is an additional part of what it means for something to be what it is. If I were able to somehow enumerate all the essential qualities of that thing, I would have to, in addition to everything else, draw another breath and say “oh yeah, and also it’s alive.” Life is part of the essence of living things. (We’ll not here go into things like dead bodies of animals, which would be its own discussion.)
Unless we would absolutely like to go into the definition of a “perfection,” it suffices here to simply say that “life” would be a perfection of living things.
So, when Catholics say that “God is a living God,” what are we referring to? The fact that He has the perfection of life (or any perfection), found in creatures, but in an uncomposed manner, which is radically different from the composed manner in which it is found in creatures.
So we can certainly say that God is the origin of life, because when we say “life” we refer to a perfection in created things that necessarily have metaphysical composition, and therefore that have that perfection of life in a composed manner. God is not “alive” in the univocal sense of the term by which we refer to living creatures. But that does not make him “dead” or non-living absolutely, because He has life in an uncomposed way.
Now, we might ask the question: Why does it matter that we’re dealing with life as predicated of God versus as part of a creature? Because when we refer to the life that is found uncomposedly in God, we do not refer just to “life,” but to every perfection that is found in him. In fact, there really isn’t in Him any distinction between them. That’s precisely the point of divine simplicity. Goodness, truth, beauty, existence – the are all the same in God, because He is uncomposed of parts. This simple, uncomposed, divine essence is not what I mean to point out when I say “Hey, that dog is alive!” But, on the other hand, we can predicate “life” of God in a qualified sense. So, we can predicate these names of God, but only analogically; we cannot predicate them of Him in the same way we predicate them of creatures.
I hope that helps.