Eternal Generation of the Son

Hi all,

A buddy of mine and I began to discuss St. Thomas Aquinas, and as we talked about him, I mentioned that Aqiunas’s work on the Blessed Trinity was profound for me and helped me so much, especially in the Person distinction and in the Eternal Generation of the Son and the Spiration of the Holy Spirit. After I had sad this, my friend said he doesn’t agree with Eternal Generation/Spiration. After questioning, he thinks that language of generation implies that there is a change in God, and doesn’t escape Arianism. He thinks that “Eternal Generation” is an incoherent term. He said, " You can’t have eternal and speak of something being prior. Prior by definition is temporal. If we hold to Aquinas, we can’t speak of Change in God because of simplicity. Generation/Procession are active terms and are in reference to change using Aquinas own argument. If we speak of change we speak of time." He went on to explain that the terms generation and procession are only in reference to the Economic Trinity but not the Ontological Trinity.
So my response was to try and emphasis the Eternity of God, and that He exists outside of time, therefore cannot change, and so terms like generation and procession have different meanings in God. That the Spirit can Proceed out of the Father and the Son eternally and there be no change since God exists in eternity and eternity being wholeness with no beginning or end as Aquinas states.

We decided to talk more later via phone call, we were only texting at this time, but I thought I’d ask real quick on here to get any thoughts or points that I could raise. I am reading Aquinas Summa on procession and some other works by theologians, but wanted to ask here as well.


What does God know? First, of necessity, he knows Himself. By way of analogy, we might say he generates an idea of himself. I have an idea of myself, but my idea is not complete, not entirely accurate. But God’s idea of himself is perfect. There is nothing in his idea of himself that is lacking, not even the aspect of personhood. So God, knowing himself, generates the Logos, the Son.

It sounds like a “process” but it isn’t because it takes no time. God the Father eternally generates the Son. Father and Son eternally spirate the Holy Spirit. There is no change; this is the nature of the divine existence from all eternity, no beginning, no end, no extension in time.

These are just my own reflections. I haven’t read Aquinas in a long time.

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Catechism of the Catholic Church affirms that the Son is “eternally born” and the Holy Spirit is “eternally from the Father and Son”:

251 In order to articulate the dogma of the Trinity, the Church had to develop her own terminology with the help of certain notions of philosophical origin: “substance”, “person” or “hypostasis”, “relation” and so on. In doing this, she did not submit the faith to human wisdom, but gave a new and unprecedented meaning to these terms, which from then on would be used to signify an ineffable mystery, “infinitely beyond all that we can humanly understand”.82

252 The Church uses
I) the term “substance” (rendered also at times by “essence” or “nature”) to designate the divine being in its unity,
II) the term “person” or “hypostasis” to designate the Father, Son and Holy Spirit in the real distinction among them, and
III) the term “relation” to designate the fact that their distinction lies in the relationship of each to the others.

246 The Latin tradition of the Creed confesses that the Spirit "proceeds from the Father and the Son (filioque) ". The Council of Florence in 1438 explains:

"The Holy Spirit is eternally from Father and Son; He has his nature and subsistence at once (simul) from the Father and the Son. He proceeds eternally from both as from one principle and through one spiration. . . . And, since the Father has through generation given to the only-begotten Son everything that belongs to the Father, except being Father, the Son has also eternally from the Father, from whom he is eternally born, that the Holy Spirit proceeds from the Son."75

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Thank you that is good stuff!

God bless

This is the critical error he makes. “Prior” doesn’t have to mean “temporal”. For one example of this, ask him to research “metaphysical priority”. (I’m not claiming it in this context, mind you, but just refuting his claim of the necessary temporality of priority.)

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Thank you!

God Bless

Is this similar to how the First Cause is not temporal, but fundamental?

You can challenge him with a proof by contradiction. Eternal Generation says that the Father begets the Son not by an act of will, but automatically by His nature. Since God is clearly outside of time, this process shouldn’t have a duration, but to illustrate the point more clearly let’s say it does. Let’s say it takes 100 billion years.

Now, let’s presume there was a time before the Son. We can call the moment of his completion point B. Now the Father is eternal, that means that if there is a point B then the Father existed infinitely before that point. Moreover we can pick any random point C that comes before B and there was an infinite amount of time before that point.

Now if the Father creates the Son automatically and not with an act of will, why doesn’t the Son exist at C? There was infinite amount before C, so His begetting should be complete by then. This is true for any point B and C. If there is a point of begetting, the Son was begotten before it. Contradiction. So there cannot have been a time before the Son.

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It seems to me that the necessity of Trinity in God is ontological. Love and Truth are of God, necessarily, essentially, intrinsically. Love requires, in the full Truth of it, the completeness/perfection of it, a lover and the beloved - two persons in relationship. The fullness, the perfection of divine love then requires at least two persons in oneness - indeed, in One.

We see the projection of this eternal and timeless interior expression of love in the eternal and timeless One God “externally”- into His creations (time and space and matter) - in the man and the woman, Adam and Eve, given together to become, to be “one flesh”. This conjugal union of the two into one flesh is ordered to create in time a child, a third person from the two, making one family. The one family is to be one in love, yet three in persons. The family reveals in a process of changes, what exists in God timelessly without change, eternally: one God, two processions, three Persons. Thus the one family in creation bears witness to the One Creator God. What God is eternally, ontologically, the family reveals in its barest simplicity, economically in time and space and matter.

But who are we to hope to probe into this divine mystery? I’m only trying to suggest how this profound mystery makes some sense to me.

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Would you be willing to explain this a little further for me? I looked up “metaphysical priority” and couldn’t find much on that.


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