Augustine wrote On the Trinity around 419 C.E.. This was after the Church had established the doctrine of the Trinity and now people were trying to defend the doctrine against heretical formulations. Besides the common charge of tri-theism, the greatest challenge came from the formulation of the trinity as presented by Arius. This Arianism, not to be confused with the Indian and Nazi idea of Aryanism, was very concerned with the authority of the Father. Arius promoted this so far as to make the Son lesser than the Father in their essential natures. After all the Son was begotten; since He was begotten, He must have been created. As something created, there was a time before He was created. Augustine sought to dispel these claims and to show how each member of the trinity have the same essential natures and how the Trinity was a necessary configuration of God. He did this in an interesting manner.

Augustine starts out book eight On the Trinity by stating some simple postulates of the Trinity:

• the greatness of the father + the greatness of the son = the greatness of the hs.
• the greatness of the son + the greatness of the hs = the greatness of the father
• the greatness of the father + the greatness of the hs = the greatness of the son
• God is the greatest Love
• God is the greatest Word
• God is the greatest Knowledge.

It is at first odd that two parts of the trinity are not greater than the remaining part. To put it in mathematical terms Augustine maintains the following:

2p = 1p.

How can this be the case? While I don”t think he explicitly says this, but if we take p to equal ∞, or infinity then I think it can work:

2∞ = 1∞

Each aspect of God is infinite. But wait, if they are each infinite, then would they not be equal to each other? Yes. That is were Augustine demonstrates the idea that each member of the trinity shares the same nature.

Augustine then uses a argument from grammar to prove that God must have a triparte nature. He examines Love. In order to have love, there must be a lover, a loved, and the action of love. Since God is the very embodiment of love, and he loved himself, he must have the three natures. In order to be love, God must at the same time be the object, the subject and the verb. Restated:

1. God is the highest love
2. Love has three parts
3. ∴ God must have three parts

Augustine repeats this basic line of reasoning for the ideas of Word and Knowledge. Since each part of the equation is dependent on the other parts of the equation, no combination is greater than the remaining part and vice versa. Likewise, the distinctions between the parts are imbued in the very nature of Love, Word, Knowledge and God. In order for their to be the word (Jesus), there must be the speaking of the word (the Spirit) and the Speaker (the father). There is no before and after here. There is no speaker until there is the speaking and their is no word until the speech and or the speaker. In this sense, we can consider the word to be begotten from the speaker and at the same time co-eternal with it. This is how Augustine by-passed Arius” charge that the son was created and therefore was lesser than the father.

Why is all of this such a big deal? Why does one have to have a correct view of God and therefore the Trinity? Augustine thought that in order to love something, one must know it. How can I love my wife if I do not know who she is? Likewise, if one does not know what God is really like, then one”s love is misplaced. Augustine says in chapter 4 of book eight, “But indisputably we must take care, lest the mind believing that which it does not see, feign to itself something which is not, and hope for and love that which is false.” In other words, if your view of God does not match the reality of God, you do not really love God and your faith is a false faith!

All of this begs the question of how one can know God. In looking around, I cannot see Him, much less observe his trinitarian nature. Augustine says we can. He draws off of the idea of imago dei, the idea that humans are made in the image of God. This, coupled with his Neoplatonism, led him to think that with the turning inward of the intellect, one could grasp the reality of God. We have a mind and we know our own mind. In order to do this, there must be a mind, the knowledge of the mind and the mind that the mind knows. This parallels God. It is this way that we can realize that as we have three parts, God also has three parts. We are a lower image of God”s true image. Augustine is quoted as saying, “As far as we know God, we are like God.” This process brings about mystical overtones. With enough introspection and prayer, one can get glimpses into the reality of God. These flashes are fleeting, however and soon we are brought back to the material world.

Cross Posted at the Unsound Argument and Hundiejo.com.