Nature and Supernature
“I don’t think the ’supernatural’ character of God is any essential part of Christian doctrine. So the fact that in some sense God could turn out to be a ‘natural’ entity doesn’t especially bother me,” writes Victor Reppert. “Obviously if you’ve got a definition of the natural that excludes the theistic God in some non-arbitrary way, that’s a whole different matter. … Words like ’supernatural’ which have strong emotive connotations with some people, have to be clarified before they are at all useful. Lewis has a definition of the supernatural as what ‘won’t fit in’ with the closed system of mindless physical causes.”
In theology we do talk about God’s nature and not God’s “supernature.” But I think that the distinction between the natural and the supernatural is useful for the following reasons. Creatures can only transform objects in their environment; God can create out of nothing. Creatures can forgive trespasses against themselves; God can forgive all sins. Creatures can give each other gifts; but only God can infuse grace directly into the soul and deify a man. In a way, then, the natural world is finite; God is infinite. In SCG Aquinas says that God’s infinity pertains to “spiritual greatness,” which “may be either in power or in goodness (or completeness) of nature. Of these two greatnesses the one follows upon the other: for by the fact of a thing being in actuality it is capable of action. According then to the completeness of its actuality is the measure of the greatness of its power.” And “if the world was made a fact from being previously no fact at all, the power of the Maker must be infinite.” (I, 43) But just as power applies to the Father, knowledge and love apply to the Son and the Holy Spirit respectively, and those are infinite, too. In ST he is more abstract, saying that “On the other hand, form is not made perfect by matter, but rather is contracted by matter; and hence the infinite, regarded on the part of the form not determined by matter, has the nature of something perfect. Now being is the most formal of all things… Since therefore the divine being is not a being received in anything, but He is His own subsistent being…, it is clear that God Himself is infinite…” (I, 7, 1)
Thus, the lack of limits on God can be contrasted with the finitude of the created world. The former can be called supernatural; the latter, natural.
But can we predict God’s behavior? On the one hand, God is completely free; on the other hand, He is His own essence, and so His actions are determined by His essence. Reppert writes that “we can generate [probabilistic expectations] based on what we take to be the character of the person we are talking about. It’s not part of anything I believe that God is completely capricious in his actions.” Well, surely, if one asks God for forgiveness, one can expect to be forgiven. But it is not that God has to do it or that the penitent can do anything to cause God to do forgive him. God alone decides who to grace and who not to. It is that in practice, actually, He forgives everyone, because of His goodness. But His sovereignty and freedom are not thereby compromised. Further, if God is, say, a utilitarian and maximizes human happiness, then we can predict His behavior based on His own rules.