Defending the Trinity


The Catechism of the Catholic Church, in paragraph 261, declares:

The mystery of the Most Holy Trinity is the central mystery of the Christian faith and of Christian life.

Belief in the Trinity is essential for salvation and should be at the top of the list when it comes to priorities in defending the faith. Yet, many Christians—many Catholics—find themselves in over their heads when the topic of the Trinity is broached by members of various quasi-Christian sects who deny it, e.g., Jehovah’s Witnesses, the Iglesia Ni Cristo, The Way International, etc.

Beginning with Sacred Scripture as a common reference point, we are going to examine three keys to explaining and defending the Trinity.

1. Jesus is God

Most often, the first problem people have with the Trinity centers on the divinity of Christ. I have found the best way to begin is to help them see what is actually very plain in Scripture: The Father is God, the Son is God, and the Holy Spirit is God. This is the essence of what we mean by “the Trinity.” And the good news is no matter who you are talking to, if they name the name of Christ, they already believe the Father is God. You’re 33% of the way there from the start!

Among the many texts of Scripture—and there are many of them—we could use to demonstrate Jesus’ divinity, I have found key texts from St. John’s Gospel to be the most effective. The reason for this, according to fathers of the Church like St. Irenaeus in the second century, and Eusebius of Caesarea, in the fourth century, is St. John wrote his gospel with an emphasis on demonstrating the errors of the fathers of Gnosticism and the heresiarch Cerinthus in particular who—among his many errors—denied the divinity of Christ (St. Ienaeus, Against Heresies, Bk. 1, ch. 26, para. 1-2; Bk. 3, ch. 11, para. 1; Eusebius, Ecclesiastical History, Bk. 3, ch. 28). Thus, it is no surprise that right from the start, “the beloved disciple” uses the plainest of terms:

In the beginning was the Word, and the Word was with God, and the Word was God… All things were made through him, and without him was not made anything that was made (John 1:1-3).

Three points concerning this text:

1. “In the beginning was…” The Greek text here employs the imperfect form of the verb “to be.” The imperfect indicates a past on-going reality. Thus, in the beginning “the Word” had already been in existence in a “past” and on-going sense. What beginning? There’s only one. The beginning. So according to the text, the Word already existed in the beginning, meaning he had no beginning. Thus, he is God. And by the way, John 1:14 makes clear who “the Word” is, when it says, “And the Word was made flesh and dwelt among us…”

2. The Word—Jesus—is also referred to as the creator. Notice, all things that were created were created through him. Genesis 1:1 says “In the beginning God created…” Jesus is plainly said to be God, the Creator. This necessarily follows when we consider Isaiah 44:24 emphatically and unequivocally declares that it is God alone who is the creator:

I am the Lord, who made all things, who stretched out the heavens alone, who spread out the earth—Who was with me?

Isaiah 45:12 adds:

Thus says the Lord, the Holy One of Israel… I made the earth, and created man upon it; it was my hands that stretched out the heavens, and I commanded their host.

3. The text plainly says, “… and the Word was God.”

In their New World Translation of the Holy Scriptures, Jehovah’s Witnesses (JW’s) translate this as “… and the Word was a god.” Their claim is Jesus is a god, not the God because the definite article (“the”) is not used before god (Gr. “theos”) when referring to “the Word.”

There are three main problems with this line of reasoning.

1) The predicate nominative in Greek does not normally take the definite article. The definite article is used in these cases to distinguish the subject from the predicate; thus, the lack of the definite article would be grammatically expected in this verse in expressing “and the Word was God.”

2) The JW’s are inconsistent. They translate the word theos (God) as Jehovah or the God numerous times when it does not have the definite article when it refers to the Father (see Matthew 5:9, 6:24, Luke 1:35, 2:40, John 1:6, 12, 13, 18, Romans 1:7, 17, 18 and Titus 1:1, just to name a few from their “New World Translation of the Holy Scriptures”).

3) Jesus is referred to as theos with the definite article many times elsewhere in Scripture. For example:

Titus 2:13:

… awaiting our blessed hope, the appearing of the glory of our great God and Savior Jesus Christ.

Not only do we see the definite article before theos, but we see the definite article + the adjective great. Jesus is not only the God; he is the great God and our Savior. The Bible is very clear that only Yahweh is both the Great God and our Savior. (See Ps. 95:3; Is. 41:4; 43:3;11; 44:6;8; 45:21; Hos. 13:4, and Luke 1:47.)

John 20:28:

Thomas answered, and said to [Jesus]: My Lord and My God.

The Greek text reads, “… the Lord (with the definite article) of me and the God (with the definite article) of me.”

I recall talking with two Jehovah’s Witnesses about this text some time ago in my living room and they ended up disagreeing with each other as to its interpretation. One said, “Thomas said that, not John, or Jesus.” The implication being Thomas got a little excited about seeing the risen Lord and exaggerated just a smidgeon about Jesus. St. John merely recorded these words—he didn’t say he agreed with them.

This is more than a stretch when we consider Jesus then affirms Thomas’s faith in the very next verse. Would he really have done this if he knew Thomas had just committed blasphemy; i.e., if he knew Thomas had wrongly declared him to be the God of the universe, when, in fact, he was not?

The other JW in the conversation claimed Thomas referred to Jesus as Lord and then to the Father as God. But there is no evidence for this in the text. Thomas is directly addressing Jesus.

Revelation 22:6:

And the Lord, the God (Gr.—ho kurios ho theos – the Lord the God, uses the definite for both terms) of the spirits of the prophets, has sent his angel to show his servants what soon must take place.

Who is the Lord God who sent “his angel” in this verse? The New World Translation says it is Jehovah—almighty God. And that is true. But Rev. 22:16, just ten verses later, reveals to us more specifically to whom verse 6 actually refers:

I Jesus have sent my angel to you with this testimony for the churches. I am the root and the offspring of David, the bright morning star.

Jesus is “the Lord God of the spirits of the prophets” according to Scripture. Thus, according to the JW New World Translation of the Holy Scriptures, Jesus is Jehovah!

John 5:17-18:

Before we cite the text, we need to know the context is one in which Jesus had healed a man on the Sabbath and then told him to “take up [his] palet and walk.” The Jews were incensed because he had broken the Sabbath. But notice Jesus’ response:

But Jesus answered them, “My Father is working still, and I am working.” This is why the Jews sought… to kill him, because he not only broke the Sabbath but also called God his Father, making himself equal with God.

It was not just that Jesus “called God his Father,” but it was the way in which he did so that was the deal-breaker. He said, in effect, “The Father works on the Sabbath, and so do I!” Translation: I am the Son who has the same nature as my Father and therefore the same divine power and prerogatives. “The Father works, you know, doing things like keeping the universe in existence… and so do I,” says Jesus.

And notice further, St. John does not say, “The Jews wrongly believed he called God his Father…” St. John affirms what Jesus Christ was actually doing when he “called God his Father.” He was referring to himself as being “equal with God.” Hear that, Cerinthus?

John 8:57-59:

The Jews then said to him, “You are not yet fifty years old, and have you seen Abraham?” Jesus said to them, “Truly, truly, I say to you, before Abraham was, I am. So they took up stones to throw at him…

In this text, Jesus refers to himself with the divine name that virtually every Jewish person in the first century would have been well acquainted with from Exodus 3:13-14:

Then Moses said to God, “If I come to the sons of Israel and say to them, “The God of your father has sent me to you,” and they ask me, “What is his name?” what shall I say to them? God said to Moses, “I am who I am.” … Say to the sons of Israel, “I am has sent me to you.”

This “I AM” formula, not copulative, sticks out like the proverbial sore thumb. It is a grammatical anomaly that could hardly have been misunderstood. Thus, some of the Jews listening considered this blasphemy and picked up rocks to stone our Lord. Our Lord would use the divine name of himself in four places in St. John’s Gospel alone (see 8:24; 28; 58; 18:5-6).

John 10:30-38:

“I and the Father are one.” The Jews took up stones again to stone him… “even though you do not believe me, believe the works that you may know that the Father is in me and I am in the Father.

Once again, Jesus reveals his divinity and the Jews want to kill him. But notice his response. He knows this is difficult for the Jews to believe so he says, in effect, “I know this is hard for you, but look at the miracles I have performed. My works prove the veracity of my message.”

2. The Holy Spirit is God

I Corinthians 2:10-11:

For the Spirit searches everything, even the depths of God. For what person knows a man’s thoughts except the spirit of the man which is in him? So also no one comprehends the thoughts of God except the Spirit of God.

St. Paul makes very clear in Romans 11:34 that no created intellect can “know the mind of the Lord.” Why? In order to “comprehend the thoughts of God,” which are infinite, one would have to possess infinite power. The fact that the Spirit of God is here revealed to uniquely comprehend “the thoughts of God” would necessarily mean that he is, in fact, God.

One must be careful here not to be too literalistic in interpreting this text. Some might say this would eliminate the eternal Son from being understood to “comprehend the thoughts of God” because the text says “no one… except the Spirit of God” comprehends the thoughts of God. That is not St. Paul’s point at all. With this sort of interpretive principle one would also have to say God would not know the thoughts of man because St. Paul said no “person knows a man’s thoughts except the spirit of man which is in him.” Well, God is three persons, so I guess the persons of the Trinity would not know the thoughts of man?

That would be absurd!

Of course God knows the thoughts of man—he knows everything. The point here is that no human person knows the thoughts of another human person. Analogously, no person apart from the Godhead can know the thoughts of God. Only God has the power to comprehend that which is infinite. That is the point.

I Cor. 6:19:

Do you not know that your body is a temple of the Holy Spirit within you, which you have from God?

According to the Summa Theologiae, Part I, Q. 27, Art. 1, St. Thomas Aquinas says it is the prerogative of God, and God alone, to have a temple; therefore, the Holy Spirit is revealed here to be God and our bodies are his temple.

Acts 5:1-4:

But a man named Anani’as with his wife Sapphi’ra sold a piece of property, and with his wife’s knowledge he kept back some of the proceeds, and brought only a part and laid it at the apostles’ feet. But Peter said, “Anani’as, why has Satan filled your heart to lie to the Holy Spirit and to keep back part of the proceeds of the land? … You have not lied to men but to God.”

According to St. Peter, lying to the Holy Spirit is equivalent to lying to God. You do the math here.

Hebrews 3:7-11:

Therefore, as the Holy Spirit says, “Today, when you hear his voice, do not harden your hearts as in the rebellion, on the day of testing in the wilderness, where your fathers put me to the test and saw my works for forty years. Therefore I was provoked with that generation, and said, ‘They always go astray in their hearts; they have not known my ways.’ As I swore in my wrath, ‘They shall never enter my rest.’”

The Holy Spirit says the “fathers” of Israel put him to the test when they put God to the test in the wilderness. He says “I” was provoked. Who was provoked and put to the test in the wilderness? Who was it who “swore in my wrath, ‘They shall never enter my rest?’” Subsequent verses make clear, and the NWT concurs, by the way, that it was almighty God. Thus, the Holy Spirit is here revealed to be almighty God.

Hebrews 10:15-17:

And the Holy Spirit also bears witness to us; for after saying, “This is the covenant that I will make with them after those days, says the Lord: I will put my laws on their hearts, and write them on their minds,” then he adds, “I will remember their sins and their misdeeds no more.”

The inspired author cites Jeremiah 31:33-34 as prophetically saying the Lord, almighty God, would establish “his” covenant with his people when the fullness of time had come. Yet, according to this same author, the author of the prophecy was the Holy Spirit. There is no way to get around it. The Holy Spirit is revealed to be almighty God.

3. Got the Trinity?

Recently, I had an extensive discussion with a Muslim about the Trinity. His problem with the Trinity was not so much with biblical texts, and obviously so, because he did not accept the Bible in the form it is in today as the word of God. Though I will say that he was remarkably interested in looking at what the New Testament had to say about the topic.

His main problem was conceptual. And I find this to be generally the case with folks who reject the Trinity. They either think Christians are claiming there are three Gods (which is what my Muslim friend actually believed to be so), or that we are teaching something that is a logical contraction, e.g., 3=1, and 1=3.

Neither is true, of course. But if we are going to help these people to understand, I find, a little background information is essential in order to establish a conceptual foundation for discussion.

Processions and Relations in God

In Catholic theology, we understand the persons of the Blessed Trinity subsisting within the inner life of God to be truly distinct relationally, but not as a matter of essence, or nature. Each of the three persons in the godhead possesses the same eternal and infinite divine nature; thus, they are the one, true God in essence or nature, not “three Gods.” Yet, they are truly distinct in their relations to each other.

In order to understand the concept of person in God, we have to understand its foundation in the processions and relations within the inner life of God. And the Council of Florence, AD 1338-1445, can help us in this regard.

The Council’s definitions concerning the Trinity are really as easy as one, two, three… four. It taught there is one nature in God, and that there are two processions, three persons, and four relations that constitute the Blessed Trinity. The Son “proceeds” from the Father, and the Holy Spirit “proceeds from the Father and the Son.” These are the two processions in God. And these are foundational to the four relations that constitute the three persons in God. These are those four eternal relations in God:

1. The Father actively and eternally generates the Son, constituting the person of God, the Father.

2. The Son is passively generated of the Father, which constitutes the person of the Son.

3. The Father and the Son actively spirate the Holy Spirit in the one relation within the inner life of God that does not constitute a person. It does not do so because the Father and Son are already constituted as persons in relation to each other in the first two relations. This is why CCC 240 teaches, “[The Second Person of the Blessed Trinity] is Son only in relation to his Father.”

4. The Holy Spirit is passively spirated of the Father and the Son, constituting the person of the Holy Spirit.

We should take note of the distinction between the “generative” procession that consititutes the Son, and the “spirative” procession that constitutes the Holy Spirit. As St. Thomas Aquinas explains, and Scripture reveals, the Son is uniquely “begotten” of the Father (cf. John 3:16; 1:18). He is also said to proceed from the Father as “the Word” in John 1:1. This “generative” procession is one of “begetting,” but not in the same way a dog “begets” a dog, or a human being “begets” a human being. This is an intellectual “begetting,” and fittingly so, as a “word” proceeds from the knower while, at the same time remaining in the knower. Thus, this procession or begetting of the Son occurs within the inner life of God. There are not “two beings” involved; rather, two persons relationally distinct, while ever-remaining one in being.

The Holy Spirit proceeds from the Father and the Son, but not in a generative sense; rather, in a spiration. “Spiration” comes from the Latin word for “spirit” or “breath.” Jesus “breathed on them, and said to them, “Receive the Holy Spirit…” (John 20:22). Scripture reveals the Holy Spirit as pertaining to “God’s love [that] has been poured into our hearts” in Romans 5:5, and as flowing out of and identified with the reciprocating love of the Father for the Son and the Son for the Father (John 15:26; Rev. 22:1-2). Thus, the Holy Spirit’s procession is not intellectual and generative, but has its origin in God’s will and in the ultimate act of the will, which is love.

As an infinite act of love between the Father and Son, this “act” is so perfect and infinite that “it” becomes (not in time, of course, but eternally) a “He” in the third person of the Blessed Trinity. This revelation of God’s love personified is the foundation from which Scripture could reveal to us that “God is love” (I John 4:8).

God is not revealed to “be” love in any other religion in the world other than Christianity because in order for there to be love, there must be a beloved. From all eternity, the Father, Son, and Holy Spirit have poured themselves out into each other in an infinite act of love, which we, as Christians, are called to experience through faith and the sacraments by which we are lifted up into that very love of God itself (Romans 5:1-5).

It is the love of God that binds us, heals us, and makes us children of God (I John 4:7; Matt. 5:44-45). Thus, how fitting it is that the Holy Spirit is depicted in Revelation 22:1-2, as a river of life flowing out from the Father and the Son and bringing life to all by way of bringing life to the very “tree of life” that is the source of eternal life in the the Book of Revelation (Rev. 22:19).

Back to the Relations in God

Scripture is a great help for us at this point. Biblically speaking, we see each of the persons in God revealed as relationally distinct and yet absolutely one in nature in manifold texts. For example, consider John 17:5, where our Lord prays on Holy Thursday:

… and now, Father, glorify me in your own presence with the glory which I had with you before the world was made.

Notice, before the creation, the Son was “with” the Father. Also, the Son addressing the Father and himself in an “I/thou” relationship is unmistakable. We have distinct persons here. “Father” and “Son” reveal a generative relationship as well. Yet, this relationship between two persons clearly has no beginning in time because it existed before the creation, from all eternity. Thus, the relational distinction is real, and personal, but as far as nature is concerned, Jesus’ words from John 10:30 come to mind: “I and the Father are one,” in that they each possess the same infinite nature.

The Holy Spirit is also seen to be relationally distinct from both the Father and the Son in Scripture inasmuch as both the Father and the Son are seen as “sending” “him.”

But when the Counselor comes (the Holy Spirit), whom I shall send to you from the Father, even the Spirit of truth, who proceeds from the Father, he will bear witness of me… (John 15:26).

… he will guide you into all truth (John 16:13).

Thus, the relational distinction is real, and personal, but the Holy Spirit, like the eternal Son, is revealed to be God inasmuch as he is revealed to be omniscient. “He will guide you into all truth.” And as we saw above, he is elsewhere revealed even more clearly to possess the same infinite and divine nature as does the Father and the Son.

The Anthropological Analogy

Analogy is the theologian’s best friend in explaining the mysteries of the Faith. And when it comes to the Trinity, there are many analogies to choose from. We will explore just two of them here that I have found helpful. In fact, it was these very two analogies that helped my Muslim friend to say the idea of the Trinity “made sense” to him, even though he wasn’t ready to leave his Muslim faith… at least, not yet.

From his famous and classic Confessions, Bk. 13, Ch. 11, St. Augustine writes:

I speak of these three: to be, to know, and to will. For I am, and I know, and I will: I am a knowing and a willing being, and I know that I am and that I will, and I will to be and to know. Therefore, in these three, let him who can do so perceive how inseparable a life there is, one life and one mind and one essence, and finally how inseparable a distinction there is, and yet there is a distinction. Surely a man stands face to face with himself. Let him take heed of himself, and look there, and tell me. But when he has discovered any of these and is ready to speak, let him not think that he has found that immutable being which is above all these, which is immutably, and knows immutably, and wills immutably.

In order to appreciate Augustine’s words, we must begin with three essential and foundational truths that undergird them. Without these, his words will fall on deaf ears.

1. We believe in one, true God, YAHWEH, who is absolute being, absolute perfection, and absolutely simple. Our belief in the Trinity does not mean God is three, or any other number of Gods.

2. Humankind is created “in [God’s] image and likeness” (cf. Gen. 1:26). From the context of Genesis 1, we know this “image and likeness” does not pertain to the body of man because God has no body. Indeed the divine nature cannot be bodily or material because there can be no potency in God as there is inherent in bodies, so this “image and likeness” must be referring to our higher faculties or operations of intellect and will.

3. It follows, then, that God is rational. He too is both intellectual and volitional.

These simple truths serve as the foundation for what I call St. Augustine’s anthropological analogy that can help us to understand better the great mystery of the Trinity:

In God we see the Father—the “being one” and first principal of life in the Godhead—the Son—the “knowing one”—the Word who proceeds from the Father—and the Holy Spirit—the “willing one”—the bond of love between the Father and Son who proceeds as love from the Father and Son. These “three” do not “equal” one if we are trying to say 3=1 mathematically. These three are distinct realities, relationally speaking, just as my own being, knowing, and willing are three distinct realities in me. Yet, in both God and man these three relationally distinct realities subsist in one being.

As St. Augustine points out, we can never know God or understand God completely through this or any analogy, but it can help us to understand how you can have relational distinctions within one being. And we can see this is reasonable.

The weakness inherent here—there are weaknesses in all analogies with reference to God—is that our knowing, being, and willing are not each infinite and co-extensive as the persons of God are. They subsist in one being in us, but they are not persons.

The Analogy of the Family

The Catechism of the Catholic Church gives us another analogy wherein we can see the reasonableness of the Trinity by helping us to see the possibility of distinct persons who possess the same nature. CCC 2205 provides:

The Christian family is a communion of persons, a sign and image of the communion of the Father and the Son in the Holy Spirit.

When we think of a family, we can see how a father, mother, and child can be distinct persons and yet possess the same nature (human), just as the Father, Son, and Holy Spirit are three distinct persons who each possess the same nature (divine).

The weakness, of course, is that in God each person possesses the one infinite and immutable divine nature, and is therefore, one being. Our analogous family consists of three beings. Again, no analogy is perfect.

But in the end, if we combine our two analogies, we can at least see both how there can be three relationally distinct realities subsisting within one being in the anthropological analogy, and how there can be three relationally distinct persons who share the same nature in the analogy of the family.

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