Chapter 27 — That God is not the form of a body

Accordingly, having shown that God is not the being of all, it can be proved in like manner that God is not the form of any thing.

For the divine being cannot be the being of a quiddity that is not its own being, as shown above. (Ch. 22.) Now that which is the divine being itself is no other than God. Therefore, it is impossible for God to be the form of any other thing.

Further. The form of a body is not its very being, but the principle of its being. But God is being itself. Therefore, God is not the form of a body.

Again. The union of form and matter results in a composite, and this is a whole in respect of form and matter. Now, the parts are in potency with respect to the whole, but in God there is no potency. (Ch. 16.) Therefore, it is impossible for God to be the form united to any thing.

Again. That which has being in itself is more excellent than what has being in another. Now every form of a body has being in another. Since, then, God is the most excellent being, as the first cause of being, (Ch. 13.) he cannot be the form of any thing.

Moreover, this can also be proved from the eternity of movement, as follows. (Cf. cc. 13, 20.) If God were the form of a movable thing, since he is the first mover the composite will be its own mover. But that which moves itself can be moved and not moved. Therefore, it is in it to be either. Now, a thing of this kind has not of itself indefectibility of movement. Therefore, above that which moves itself we must place something else as first mover, which confers on it perpetuity of movement. And thus God, who is the first mover, is not the form of a body that moves itself.

This argument is useful for those who hold the eternity of movement. Yet if this if not granted, the same conclusion may be drawn from the regularity of the heavenly movement. For, just as that which moves itself can both be at rest and be moved, so can it be moved with greater or less velocity. Therefore, the necessity of uniformity in the heavenly movement depends on some higher principle that is altogether immovable, and which is not the part, through being the form, of a body which moves itself.

The authority of Scripture is in agreement with this truth. For it is written in the Psalm: your magnificence is elevated above the heavens (Ps 8:1); and: he is higher than heaven—what can you do? . . . His measure is longer than the earth, and broader than the sea (Job 11:8–9).

Hence we are able to refute the error of the pagans who asserted that God was the soul of the heaven or even the soul of the whole world. (ST I.3.8.) This error led them to defend the idolatrous doctrine by which they said that the whole world was God, not in reference to the body, but to the soul, even as man is said to be wise in reference not to his body but to his soul. Supposing this, they fancied that divine worship is not unduly shown to the world and its parts. The Commentator also says (Metaphysics 11) that this occasioned the error of the Zabian people, that is, of idolaters, namely, because they asserted that God was the soul of the heaven.