Why is God a Trinity?


This I suppose is the most basic of questions. I have always solemnly believed in the Trinity, but wondered why it had to be three persons. God is “simple” in that He is the source of all so why the complication of three persons? Could it be because that is the logical progression of love, which is also what God is? By that, I mean that love by definition must be shared, hence the Father and the Son provide that relationship where the necessary sharing happens. The love itself is of course manifested as the Holy Spirit because love itself is creative (granted that may not be not the best theological description). Therefore, the most basic example of a God of love and creation is actually three persons in one God. That’s all I can figure. Does any of it make sense? Also, as I think about this, what is the truest definition of God, “creator” or “love”?



I think you got it.:thumbsup:

God is love. :slight_smile:

It’s all about love.

Creation is an act of love.

The Incarnation was an act of love.

You get the point :slight_smile:


Hmm. C.S. Lewis made an arguement about this in Mere Christianity. Maybe you could check that out, if no one has any better ideas.


Here’s my guess…

I’ve been reading Theology for Beginners by Frank Sheed at the recommendation of some posters in these forums. I haven’t understood it completely (I think I need to read the book again), but I’ll have a go…

God is a spirit. Therefore, like all spirits, he knows and he loves. His knowledge and his love inherit his divine nature. His divine nature is infinite, and can not be separated. Therefore, his knowledge and his love posses the total divine nature.

His knowledge, aka The Word, became man; Jesus.

His love is the giver of life; The Holy Spirit.

Therefore, Jesus and the Holy Spirit, are God because they completely posses the total divine nature.

Therefore, God - who is the Creator - with a spirit that knows and loves - will have to be a Trinity.

:twocents: I could be wrong…


I recommend the book Theology for Beginners by F.J. Sheed. It has an excellent chapter on the Trinity.


Hmmm… I just like to add to my post # 4 above. Because I re-read your original post, and I just thought of the Filioque - you know, that extra bit that was added in the Apostles Creed, where it is stated that the Holy Spirit proceeds from the Father and Son (as opposed to just the Father).

I wonder, if before the world was created, what was it that God loved, if not his Son?

Hmmm… I think I read something about that in Frank Sheed’s “Theology for beginners”. Boy, I think I need to re-read that book.


CZ–great explanation!

St. Gregory Nazienzan’s Orations on the Trinity are quite good too.


Thanks folks, it is reassuring to know my thinking is at least on the right track. I think the question of how could God “love” if there is nothing outside of himself to love (i.e. “in the beginning”), is a great way to introduce someone to the idea of the Trinity if they don’t know or accept it yet. I gotta look into that Sheed book - it sounds like a treasure! :thumbsup:



Another good book on the subject is *First Comes Love *by Scott Hahn. It relates the love in a family to the love in the Trinity.


This Trinity teaching of the christian faith is very hard to grasp. During my younger days, I just believed, as a catholic, because it’s been a dogma, but deep in my heart I craved for the enlightenment to shed light on my bewildered thoughts. I’d been thinking why my arithmetic cannot be applied to this Trinity. In my elementary grades we were taught that 1+1+1 = 3, but in the teaching of the Trinity 1+1+1= 1. :smiley:


There are many theories, but the Trinity is a mystery of the faith at heart and not accessible by human reason along. If it doesn’t “make sense”, it’s probably because it isn’t meant to—the nature of God is not required to be fully understood by His creatures.


Interesting analogy. I was just reading last night that a man approached the Church looking to convert as he claimed to have a mathematical proof of the Trinity. He was refused, as believing that a mathematical proof of the Trinity was possible is to violate dogma, and to violate dogma is not to be Catholic.

There is great wisdom in this, it seems to me. Man must not be so proud as to think he can rationalize God.


At the begining of the book of John we learn that the “Word” is someone, not something.

1 In the beginning was the Word: the Word was with God and the Word was God.

2 He was with God in the beginning.

3 Through him all things came into being, not one thing came into being except through him.

4 What has come into being in him was life, life that was the light of men;

5 and light shines in darkness, and darkness could not overpower it.

And if you look at the begining of the book of Genesis you’ll notice God the Father, God the Son and God the Holy Spirit.

Genesis 1
1 In the beginning God created heaven, and earth.

God the Father

2 And the earth was void and empty, and darkness was upon the face of the deep; and the **spirit of God **moved over the waters.

God the Holy Spirit

3 And God said: Be light made. And light was made.

The Word of God, before He came in the flesh, Jesus

26 God said, “Let us make man in **our **own image, in the likeness of ourselves, and let them be masters of the fish of the sea, the birds of heaven, the cattle, all the wild animals and all the creatures that creep along the ground.”

The Holy Trinity

Back to the book of John

14 And the Word was made flesh, and dwelt among us, (and we saw his glory, the glory as it were of the only **begotten of the Father,) **full of grace and truth.

15 John beareth witness of him, and crieth out, saying: This was he of whom I spoke: He that shall come after me, is preferred before me: because he was before me.
16 And of his fullness we all have received, and grace for grace.

17 For the law was given by Moses; grace and truth came by Jesus Christ.

18 No man hath seen God at any time: the only **begotten Son **who is in the bosom of the Father, he hath declared him.

Begotten =1. spawn, sire, breed, father, (esp. of a male parent) to procreate or generate (offspring).

Our children share our nature,they are human beings because we are.

Jesus shares His Fathers nature, He is God because His Father is God.

Jesus also shares His mothers nature,He is human because she is human.

All of us have one nature we are human.

Jesus has two natures He is both human and Divine. because of His parents.

And because Jesus is one with His Church His Church is both human and Divine.

We make up the body of His Church that is the human part. Jesus being one with His Church, and the Holy Spirit guiding it. That is the Divine part.

Through Scripture, Tradition and the Magisterium. This is how I know Jesus is both, at the same time, human and Divine.


LT, you’re figuring right along with John Paul II who spoke of this Mystery as one revealing that God, while One, is never alone. God is a Community of Persons, and it is in this Divine Communion that man finds the fulfillment of his desire for communion with another. It is only because of the “First” Communion of the Divine Persons that our communion is possible with one another and with the Divine Persons. These Persons have no need for Communion with one creature, let alone millions, yet out of the fruitfulness of the impenetrating Love within the Godhead we have been created in order for us to participate in that Divine Communion (primary) and communion with each other (secondary).

“God in His deepest mystery is not a solitude, but a family, since He has in Himself fatherhood, sonship, and the essence of the family, which is love.”

“A great mystery, a mystery of love, an ineffable mystery, before which words must give way to the silence of wonder and worship. A divine mystery that challenges and involves us, because a share in the Trinitarian life was given to us through grace, through the redemptive Incarnation of the Word and the gift of the Holy Spirit: ‘Anyone who loves me will be true to my word, and my Father will love him; we will come to him and make our dwelling-place with him’ (Jn 14: 23).” John Paul II.



While I can certainly relate to your experience with wanting to make at least some sense of a truly awesome tenet of the Holy Faith, I have come to believe that it’s okay to just sometimes rest in faith. :sleep:

It’s kinda like being a little kid. Our parents tell us something and we believe them. We then find rest in that belief because we have no reason to doubt their words. :hug3:

Over the tumultous “ride” that I have gone to in deciding to returning to the Catholic Church, I have come to realize that in the end it doesn’t matter whether I understand what God has said in His revelation to mankind. :bible1:

In the end I should emulate a little child, and believe what my heavenly Father says is true, regardless of whether I can grasp it on a rational basis. :slight_smile:

But that is my experience and it’s just my :twocents:


I like to add one more point to this exegesis. The next verse says:

27 God created man in his image; in the divine image he created him; male and female he created them.

So we can see that the image of God is not male alone or female alone. We are the image of God when male and female are joined in holy matrimony and are fruitful with child. The image of God is a loving family.


No, in the teaching of the Trinity it is more like 1X1X1=1. :slight_smile:


Hi Joero; I think Prayer_Warrior has a valid point.

We believe God is one because of His divine nature. Divine nature is infinite; It can not be added, it can not be divided, it can not be separated, it is just itself; Without beginning, without boundary, without limitation, without time, it just exists. It is hard, if not impossible, for us humans to understand because we have a finite nature.

The Father, Son, and Holy Spirit possess the divine nature completely; They don’t posses a copy of it. They don’t posses a part of it. They just possess in full the infinite divine nature.

So, it is true;
1 person with an infinite divine nature

  • 1 person with an infinite divine nature
  • 1 person with an infinite divine nature
    = 3 persons with an infinite divine nature
    = 1 x Trinity
    It is also true;1 infinite divine nature x 1 x 1
    = 1 infinite divine nature
    = 1 God


Hi, all of you there ! :slight_smile:

During our religion class, I brought this question to our religion teacher, a nun, and I went to the blackboard to write 1+1+1 = 3 and after I wrote that I threw a question at her saying " why, sister, that this mathematical procedure could not be applied to theTrinity because if we add the three persons, and each person is God in its divinity, why would it come up to a one God, meaning 1+1+1= 1 ? It is a wrong mathematical procedure?
Then, our religion teacher moved closer to the blackboard and wrote a number 1 and said “one plus one plus one equals one” (while saying that she marked on the same spot of the number 1 and it becomes bolder and looks like this 1. Then, she called my attention, "alright, Joero, how many 1 can you see? I said “only one !” Then, she said "see !!! there’s only one !"
I said to myself “oh my God! :eek: my religion teacher is wiser!” :eek:


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