THE RATIONAL SOUL NOT DERIVED FROM GOD'S SUBSTANCE
However, we are not to imagine that the rational soul is derived from the substance of God, as some have erroneously thought. We demonstrated above that God is simple and indivisible. Therefore He does not join the rational soul to a body as though He had first severed it from His own substance.
Furthermore, we pointed out above that God cannot be the form of any body. But the rational soul is united to the body as the latter's form. Hence it is not derived from the substance of God.
Besides, we showed above that God is not moved either in Himself or by reason of some other thing that is moved. But the contrary of this is observed to take place in the rational soul, which is moved from ignorance to knowledge, from vice to virtue. Accordingly the soul is not of the substance of God.