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Defending the Trinity

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 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 (Jehovah’s Witnesses, the Iglesia Ni Cristo, The Way International, etc.).

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

Jesus is God

The first problem most people have with the Trinity is the divinity of Christ. I have found the best way to begin is to help them see what is 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.” The good news is, no matter who you’re talking to, if they name the name of Christ they already believe the Father is God. You’re 33 percent of the way there from the start!

Among the many texts of Scripture we could use to demonstrate Jesus’ divinity, I have found key texts from John’s Gospel to be the most effective. The reason for this, according to Fathers of the Church—such as Irenaeus in the second century and Eusebius in the fourth century—is that John wrote with an emphasis on demonstrating the errors of the fathers of Gnosticism who denied the divinity of Christ.

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 Word.”The Greek text here employs the imperfect form of the verb to be, indicating a past, ongoing reality. 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:
  3. The text plainly says, “… and the Word was God.”

In the Jehovah’s Witnesses New World Translation of the Holy Scriptures, this istranslated as “and the Word was a god.” Their claim is that Jesus is a god, not the God, because the definite article (“the”) is not used before god (Greek, 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. JWs translate the word theos (God) as Jehovah (or the God) numerous times when it doesn’t 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; 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 (see Titus 2:13; John 5:17-18, 8:57-59, 10:30-38. 20:28; Revelation 22:6).

The Holy Spirit is God

St. Paul tells us:

[T]he 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 (1 Cor. 2:10-11).

Paul makes clear in Romans 11:34 that no created intellect can “know the mind of the Lord.” Why not? 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 comprehend “the thoughts of God” would mean necessarily that he is, in fact, God.

One must be careful not to interpret this text literally. 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?

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.

Here are only three of the several Scripture passages that support this point (see also Jeremiah 31-33-34, Hebrews 10:15-17):

1 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), 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.

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 . . . 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? Subsequent verses make clear—and the NWT concurs, by the way—that it was almighty God.

Got the Trinity?

Recently, I had a long discussion with a Muslim about the Trinity. His problem with was not so much with biblical texts—and obviously so, since he didn’t accept the Bible as the word of God. He was, however, remarkably interested in looking at what the New Testament had to say about the topic.

His main problem was conceptual. And I find this generally to be the case with folks who reject the Trinity. They think Christians are claiming there are three Gods (which is what my Muslim friend thought) or that we are teaching a logical contradiction, (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. The Council of Florence (A.D. 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. Those four eternal relations are:

  1. The Father actively and eternally generates the Son, which constitutes 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. This is why the Catechism teaches, “[The Second Person of the Blessed Trinity] is Son only in relation to his Father” (CCC 240).
  4. The Holy Spirit is passively spirated of the Father and the Son, constituting the person of the Holy Spirit.

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: “[A]nd now, Father, glorify me in your own presence with the glory which I had with you before the world was made.”

Notice that 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 the Father and the Son in Scripture inasmuch as both the Father and the Son are seen as “sending” “him.”

But when the Counselor [the Holy Spirit] comes, 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).

So 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 do the Father and the Son.

The anthropological analogy

Analogy is the theologian’s best friend in explaining the mysteries of the Faith. We will explore just two Trinitarian analogies that I have found helpful. In fact, it was these 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.

In his classic Confessions, 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 (book 13, ch. 11).

In order to appreciate Augustine’s words, we must begin with three 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” (Gen. 1:26). From the context of Genesis 1, we know this “image and likeness” do not pertain to the body of man, because God has no body. Indeed, the divine nature cannot be 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 also 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 mathematically; they are rather 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 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—is that our knowing, being, and willing are not each infinite and co-extensive as are the persons of God. 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 whereby we can see the reasonableness of the Trinity by seeing the possibility of distinct persons who possess the same nature: “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” (CCC 2205).

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 in 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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