1. Having demonstrated that God exists, St. Thomas proceeds to discuss the divine essence. Recall that the order of investigation is: Existence (q.2), Essence (qq.3-14), Operations (qq.15-26), Inward Processions (qq.27-43), Outward Processions (qq.44-119).
2. Within his discussion of the divine essence, he divides the topic into three parts: what God is not (qq.3-11), how he is known to us (q.12), and how we name him (q.13).
3. In discussing what God is not, Thomas systematically excludes characteristic features of creatures from God: composition (q.3), imperfection (qq.4-6), finitude (qq.7-8), mutability (qq.9-10), plurality (q.11).
4. The of these questions concerns the simplicity of God, whether God is composed of different parts. Thomas uses the divine simplicity as the middle term in a variety of other more significant deductions, so while readers might be inclined to skim past this question, it is in fact one of the most important in the Summa.
5. In the first article, Thomas asks whether God is a body. Against God’s incorporeality he puts forward five objections. All of the objections are from metaphorical references to God in scripture. The first is from the references to his three-dimensionality (height, breadth, depth). The second is from references to his visible likeness (“let us make man in our image”). The third is from references to God’s body parts (arms, eyes, hands). The fourth is from references to his posture (sitting, standing). The fifth is from references to his location (wherefrom and whereto).
6. In the Sed Contra, he cites Jesus in John’s Gospel, telling the woman at the well that God is a spirit, and therefore must be worshipped spiritually, and not just in one place.
7. In the Corpus, he offers three arguments: First, that no body causes motion without being moved, as is obvious from experience, but God is an unmoved mover, as already shown. (Note that the standard translation of this first argument is incorrect.) Second, that act is prior to potency, because potency can only be realized by the introduction of some prior act. Since God is the first being, if he had potency, it would require a prior agent to be actualized. Therefore he is without potency. And since all bodies are in potency to locomotion, God cannot be a body.
8. Thomas’s third argument is from God’s nobility. Bodies are nobler on account of their union with souls, but this shows that souls are in themselves nobler than bodies. God is the most noble being, so he could not be a body. This argument makes modern readers uncomfortable, but Thomas takes for granted the obviousness of degrees of nobility in things, and that the living is higher than the nonliving. These are not difficult assumptions to accept, in themselves, but the argument would not be readily accepted by contemporary skeptics, for example.
9. In the replies to the objections, Thomas gives the spiritual sense of each category of scriptural sense. Briefly: The dimensions of God signify his knowledge, eternity, knowledge, love, incomprehensibility, power, omnipresence, etc. The image of God in man signifies his superiority over all other animals by virtue of intelligence. The body parts of God signify various actions (the eye for knowledge, the hand for power or judgment, etc.), likewise with his posture. Finally, descriptions of God’s place are used to symbolize the disposition of the soul or the adversion of the mind, which can be closer or further from God spiritually by its actions.
Outline of Article
—God is described in scripture as having various corporeal qualities: dimension, image, body parts, posture, location.
—John 4:24, "God is a Spirit"
—Bodies do not cause motion without being moved.
—Bodies are in potency to motion, but God as prime mover is not in potency in any way.
—Bodies are less noble than spirits, and God is the noblest being.
—The references in scripture to God's corporeality symbolize various acts, qualities, and dispositions of God, or of creatures to God.