Biblical theism and classical theism have much in common, particularly the position that God is different in kind from all of creation. But there is an implicit principle of classical theism that I would put this way: “God only does what only God can do.” For example, because only God is transcendent, it is consistent with this principle that God creates from nothing.
“An architect of the universe would have to be a very clever being, but he would not have to be God…” Maurice Holloway, S. J., An Introduction to Natural Theology, pp. 146-47 (quoted here). However, there’s more than the existence of God at issue; there’s also the existence of mankind as a created kind, rather than a taxon only different in degree from other taxa.
Classical theists assert that there is only one causal act in God by which he causes ex nihilo whatever exists apart from himself. That is, God does not take something already existing and make it into something else. Why not? Because that would be doing something that a creature could possibly do.
They aver that if God designs creation, then he is doing something that others can do in some measure, which would be beneath God, as if God were merely a demiurge. Thus this view of God deprecates any divine association with design.
It’s like saying, “A human is different in kind from an ant, so since ants can crawl around, humans would never crawl around because that would be different in degree, not in kind.”
Wrong. To be different in kind does not entail being different in every respect.
God could take something already existing and make it into something else. Whether or not he has done so is another matter. The biblical theist insists that God has done so because that is what the Bible reveals.
God not only creates something from nothing but he also designs something from something previously existing. Genesis chapter 1 not only states, “And God said, “Let there be light,” and there was light.” (verse 3). It also states, “And God separated the light from the darkness.” (verse 4)
Genesis chapter 2 states, “the Lord God formed the man of dust from the ground and breathed into his nostrils the breath of life, and the man became a living creature.” (verse 7) And then, “the Lord God planted a garden in Eden, in the east, and there he put the man whom he had formed.” (verse 8) And further, “the rib that the Lord God had taken from the man he made into a woman and brought her to the man.” (verse 22).
An unprejudiced reading of these chapters shows God creating from no prior existing thing (e.g., light) as well as from some prior existing thing (e.g., by reforming a part of Adam).
At this point the classical theist may well bring up primary and secondary causality. God could have caused things to exist from nothing (primary), and then those things could cause existing things to change (secondary). That certainly happens but is not necessarily the only thing that happens.
The classical theist needs to show that God only creates from nothing and in no case from something. Or show that God’s primary causality is the only final causality, and all other causes are secondary causes.
But both final and formal causes are primary causes. Secondary causes are the efficient and material causes. God causes both the end and the form of creation. Since formal causation is an act of design, God is a designer as well as a creator.
Teleological causation is from nothing. Formal causation is from something, whether it is an end (a telos) or a beginning (a material).
Genesis shows God causing kinds of creatures to exist, not mere taxa that differ in degree only. That entails design, a forming of something from something already existing. God does that in the act of creation.