In my conversations with Catholic and other Christian friends I have noticed there seems to be a large difference in how they speak of God in a spiritual sense and how they speak of God in argument. The former is a God of love and service who cares and can intervene in human affairs like a parent of sorts; the latter is Aristotle’s God that is pure act, forever unmoving and existing only as the prime mover of all things. I have become troubled by this inconsistency.
May I offer a few comments? Some are forgetting the key to the first way. It is precisely this. Thomas says "…whatever is in motion is put in motion by another, for nothing can be in motion except it is in potentiality to that toward which it is in motion; whereas a thing moves in as much as it is in act.
This means that " …a certain potentiallity is actualized by something whose potentiality is itself actualized by something whose potentiality is itself actualized by ( something whose potentiality is actualized by, etc ) and so on…such a series can only possibly terminate in something which is not reduced to act or actualized by anything else, but which just isin act or actual and thus " unmoving "…Eventually this regress must terminate in something which here and now actualizes potentialities without itself being actualized, an unmoved mover. " ( Edward Feser, in Aquinas, pg 73)
So the Unmoved Mover ( Aristotle’s Prime Mover as interpreted by Aquinas) is Actus Purus or pure actuality having no potentiality whatsoever. Such a being, a Pure Actuality is immediately recognized by Christians as God.
Several things must be seen about such an Acutality. First, it must be outside the ontological members of the series since it is a pure actuality having no potentiality whereas the members of the series are all beings composed of actuality and potentiality.
Secondly such a series could actually be eternal since the Unmoved Mover itself is outside the series ontologically. One of our posters objected that an Unmoved Mover would not be required if the series was eternal. This answers that objection. It must be remembered that Thomas designed the proof to account for the possibility of an eternal universe. His proof shows that even if the universe is eternal an Unmoved Mover is required. What most people forget is that the Unmoved Mover is ontologically outside the series. Thomas could have made this more clear but he does explain himself in other places. However it is clear from the argument he gave if you think about it thoroughly.
Now it can be shown that all the proofs conclude in a First Something which can indeed be reduced to a Pure Actuality and thus can be identified easily as the Christian God. Thomas will go on in Book 1, Question 3 and following to analyize the nature of the Unmoved Mover, etc. or God. He will show that the First Being, God, has all the characteristics of the Christian God, including Intelligence, Will, Justice, Love, Goodness, Mercy, Personhood, etc. is Omnipotent, Omnescient, Omnipresent and, the creator, maintainer, and orderer of all that exists.
Some friends argue that God the Father is the unmoving aspect of the Trinity, while Christ is able to move, acting in both the material and immaterial realm as a conduit of sorts due to his dual nature. This might work, but it seems to leave the Father as an impersonal force that isn’t relational in the sense that scripture implies.
From what I included above, it should be clear that Thomas’ Unmoved Mover is not an impersonal force. Reason alone can lead us only so far. It goes far enough to see that the Unmoved Mover is easily identified with the God of Revelation who is indeed personal, they are one in the same Beings.
How is God unchanging and at the same time loving, intervening, etc.?
See remarks above.
