By James M. Rochford

The word “Trinity” is not used in the Bible, but the concept is certainly present throughout Scripture. The term “Trinity” was not used until Tertullian (AD 200), who used the Latin word trinitas (pronounced TRIN-eeh-toss) to describe the three persons of the Trinity.[1]

The doctrine of the Trinity is not illogical, but it is difficult to wrap our minds around. However, as believers in an infinite and transcendent God, this shouldn’t surprise us. This is a sign that we are encountering the true God, who is mysterious and complex, rather than a human projection or creation. About his own nature, God himself said, “To whom would you liken Me and make Me equal and compare Me, that we would be alike?” (Isa. 46:5). Shouldn’t we expect a bit of mystery when studying the nature of God, if this verse is really true? Theologian Millard Erickson comments,

The Trinity must be divinely revealed, not humanly constructed. It is so absurd from a human standpoint that no one would have invented it. We do not hold the doctrine of the Trinity because it is self-evident or logically cogent. We hold it because God has revealed that this is what he is like.[2]

Of course, while Christians believe the doctrine of the Trinity is mysterious, this doesn’t exclude careful thinking or curiosity. Consider when Sherlock Holmes surveys a mysterious crime scene. He never throws his hands up in defeat saying, “Well, it’s a mystery who killed him… I guess I’ll just go home and play my violin and drink tea until it’s time for bed.” Instead, the mysterious nature of the murder causes him to pursue more investigation—not less. Similarly, when Christians use the term “mystery” to describe the Trinity, they shouldn’t use this as a guise for lazy thinking or an apathetic attitude.

Unity and Diversity in the Godhead

The Bible never uses the term “Trinity.” But then again, it also never uses the terms “theocratic” or “personal relationship” or even “Bible.” Like all of these words, the term Trinity accurately captures what the Bible teaches concerning God’s nature. Similarly, when we read Moby Dick, we might never read the words “pride” or “revenge” (although we might; I haven’t checked). But even if these words never appeared in the book, the words would aptly describe the plot of Moby Dick, where Captain Ahab maniacally seeks to kill his white whale. Likewise, the Trinity is an accurate description of what Scripture teaches regarding the nature of God. Consider these three propositions below:

(1) The Father, Son, and Holy Spirit are all DISTINCT PERSONS

(2) The Father, Son, and Holy Spirit are all FULLY GOD

(3) There is only ONE GOD

If these three propositions are true, it would follow logically and necessarily that the Trinity is true (i.e. There is one God, who exists in three distinct persons). Let’s consider the first proposition:

PROPOSITION #1: The Father, Son, and Holy Spirit are all DISTINCT PERSONS

If we deny this biblical teaching, we fall prey to Modalism. Modalism (sometimes called “Sabellianism” after Sabellius in the 3^rd century AD) teaches that God merely appears as distinct persons. Instead of a Trinitarian view of God, modalism is a Unitarian view. It holds that there is one God and one person in the Godhead. Modalists often give the illustration of a man, who plays three different roles in his life. For instance, he might appear in church as an elder, in court as a lawyer, and at home as a father. But he is still the same man in all three roles. Modalists hold that God appeared as the Son on Earth, but he is the same person as the Father in heaven. Modern groups such as the United Pentecostals are modalistic, denying the Trinity.[3]

However, when we survey the Bible, we see that God is not play-acting as three distinct persons; instead, he is made up of three distinct persons. For instance, Jesus prayed directly to the Father as a separate being (Mt. 11:27; 26:39; Jn. 14:16-17). We can hardly make sense of the “high priestly prayer” unless the Father and Son are separate persons (Jn. 17). Elsewhere, Jesus spoke of the Father and the Holy Spirit as distinct from himself (Lk. 11:13; Jn. 14:26; 15:26). Jesus told us to baptize new believers “in the name of the Father and the Son and the Holy Spirit” (Mt. 28:19). Paul spoke of all three persons of the Trinity, when he wrote, “The grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit, be with you all” (2 Cor. 13:14). Likewise, Peter spoke of believers being chosen by “God the Father, by the sanctifying work of the Spirit, to obey Jesus Christ and be sprinkled with His blood” (1 Pet. 1:2). 14:26). At Jesus’ baptism, we read, “[Jesus] saw the heavens opening, and the Spirit like a dove descending upon Him; ¹¹ and a voice came out of the heavens: ‘You are My beloved Son, in You I am well-pleased’” (Mk. 1:10-11).[4]

While the three persons are distinct and separate centers of consciousness, they also agree with one another in their decisions and actions. We see this in the creation of the universe (Gen. 1:1-2; Jn. 1:1-3), Jesus’ resurrection (Gal. 1:1; Acts 2:24, 32; Rom. 1:4; Jn. 2:19; 10:18), and the indwelling of believers (Jn. 14:16, 18, 23; Rom. 8:9).

PROPOSITION #2: The Father, Son, and Holy Spirit are all FULLY GOD

If we deny this biblical teaching, we fall prey to Arianism. Arianism (named after Arius from the 4^th century AD) taught that Jesus was not God—only a created being. Jehovah’s Witnesses, Mormons, and Oneness Pentecostals are all examples of modern Arianism. All three groups hold that Jesus was not fully God, and thus, they would be Arian in their theology. However, by contrast, the Bible teaches that all three members of the Trinity are fully God.

First, the Father is FULLY GOD. Psalm 89:26 states, “You are my Father, my God, and the rock of my salvation.” Isaiah 63:16 states, “You, O LORD, are our Father.” Sometimes God is called the Father, but other times, the Father is simply called “God.” For instance, Paul writes, “God sent forth His Son.” We will not survey any more verses to justify the fact that the Father is fully God, because most groups (even Christian cults) would agree on this point.

Second, the Holy Spirit is FULLY GOD. Peter says, “Ananias, why has Satan filled your heart to lie to the Holy Spirit? …You have not lied to men but to God” (Acts 5:3-4). Here Peter equates lying to the Holy Spirit with lying to God himself. John writes of those who are “born of God” (1 Jn. 3:9), but elsewhere, he says we need to be born “of the Holy Spirit” (Jn. 3:5). Moreover, the Holy Spirit is eternal (Heb. 9:14; Jn. 14:16), omnipresent (Ps. 139:7-8), omniscient (1 Cor. 2:10-11), and he is lumped together with other known persons in the Godhead (1 Cor. 12:4-6; 2 Cor. 13:14; 1 Pet. 1:2; Mt. 28:19).

Third, the Son is FULLY GOD. Paul tells us that Jesus “existed in the form of God” (Phil. 2:6), and “in Him all the fullness of Deity dwells in bodily form” (Col. 2:9). John writes, “In the beginning was the Word, and the Word was with God, and the Word was God” (Jn. 1:1). It is the person of Christ that different cult groups and Unitarians (i.e. one person monotheisms) deny as fully distinct or fully God. For a full treatment of the deity of Christ, see our earlier article “Defending the Deity of Christ.”

PROPOSITION #3: There is only ONE GOD

If we deny this biblical teaching, we fall prey to Tritheism—the belief in three gods. Wayne Grudem writes, “Few persons have held this view in the history of the church.”[5] But if we affirm propositions one and two, it could lead to a belief in three gods, which would be polytheism.

Of course, the Bible clearly teaches that there is only one God. Isaiah 45:6 states, “There is no one besides Me. I am the Lord, and there is no other” (cf. Isa. 44:6-8; 45:21-22; 1 Kings 8:60; Deut. 4:39; Ps. 96:5). Jesus wanted his followers to the “only true God” (Jn. 17:3). Likewise, Paul writes, “There is one God” (1 Tim. 2:5), “God… is one” (Rom. 3:30), and “There is but one God, the Father, from whom are all things and we exist for Him” (1 Cor. 8:6). Likewise, James writes, “You believe that God is one. You do well” (Jas. 2:19).

Conclusion

If all three of these propositions are true, it would follow logically and necessarily that the Trinity is true. In defining the doctrine of the Trinity, it is imperative to use careful definitions. This Christian doctrine is essential to our faith, but it is often misunderstood or improperly communicated.

Objections to the Trinity

While the biblical evidence for the Trinity is ample, skeptics and cultists often raise philosophical objections against this theological view of God. Let’s consider a number of objections to the Trinity.

OBJECTION #1: “If the Father, the Son, and the Holy Spirit are all God, then doesn’t this mean that there are three Gods in Christianity? If so, then how can it still be considered monotheistic?”

This is not a logical contradiction. We are not saying that three gods are equal to one God. Nor are we saying that three persons are equal to one person. Instead, we are saying that within the one God there exists three separate persons. The three persons of the Trinity are the same in regards to what they are (i.e. God), but they are distinct in regards to who they are (i.e. separate persons). This distinction is important when understanding how the Trinity is monotheistic.

The whatness of the persons in the Trinity is multiplied (making one God). Divinity is a quality; therefore, it should be multiplied qualitatively like this:

1 x 1 x 1= 1.

By contrast, their whoness is added (making three persons total). Persons are a quantity; therefore, they are added quantitatively like this:

1 + 1 + 1= 3.

Thus no logical contradiction is warranted.

OBJECTION #2: “If the Father is identical to God and the Son is identical to God, then doesn’t it logically follow that the Father is identical to the Son?”

If this statement is true, we could quickly get into theological trouble. For instance, the Father did not die for sins. The Son did. It was not the Son, who poured out wrath at the Cross. It was the Father. How then do we answer this conundrum?

In order to answer this objection, we need to distinguish between the identity and the property of God. The three members of the Trinity are separate in identity, but they are the same in property. For example, I am identical to a human being, and my father is identical to a human being. But I am not identical to my father. We are the same in property (i.e. humanness), but separate in identity (i.e. father and son). Of course, this analogy fails because we are not one in being (as God the Father and God the Son are one in being), but hopefully it helps to distinguish identity from property regarding this objection.

OBJECTION #3: “The doctrine of the Trinity is a NT invention, and we cannot find it anywhere in the OT.”

Before we offer allusions to the Trinity in the OT, we should point out that our expectation might be skewed from the start. The NT often elucidates many doctrines that are vague or even concealed in the OT. For instance, while heaven and hell are supported in the OT (Dan. 12:2; Isa. 26:19), they are not as clear as in the NT. Since the Bible is progressive revelation, we should expect to see most doctrines coming in to focus most clearly in the NT after the coming of Christ (Heb. 1:1-2). This being said, let’s consider some of the allusions to the Trinity in the OT.

Genesis 1:26-27

(Gen. 1:26-27) Then God said, “Let us make man in our image, in our likeness, and let them rule over the fish of the sea and the birds of the air, over the livestock, over all the earth, and over all the creatures that move along the ground.” ²⁷ So God created man in his own image, in the image of God he created him; male and female he created them.

God refers to himself in the plural (“let us” and “in our”), yet the verb (“said”) is singular.^[6] The Hebrew suffix im makes the noun plural (sort of like adding an “s” to the end of a noun in English). This makes Elohim roughly translated “the Mighty Ones” which you’ll notice is plural. Jewish interpreters sometimes argue that this refers to the angelic host. However, humans are said to be made in God’s image—not an angelic image. The Bible never teaches that humans are made in the image of angels. While we do not believe that this passage proves the doctrine of the Trinity (see comments on Genesis 1:26-27), we believe that it is consistent with this doctrine.

Psalm 45:6-7

(Ps. 45:6-7) Your throne, O God, is forever and ever; a scepter of uprightness is the scepter of Your kingdom. You have loved righteousness and hated wickedness; therefore God, Your God, has anointed You with the oil of joy above Your fellows.

This psalm is addressed to the “King” of Israel (Ps. 45:1), and yet, the psalmist calls the king God (Hebrew elohim)! How can a human king carry this moniker? Only a divine King could rightfully carry this title. Michael Brown tells this anecdote, regarding Psalm 45:

When I first started studying Hebrew in college, I asked my professor, a very friendly Israeli rabbi, to translate for me the words kis’aka ‘elohim ‘olam wa’ed. He replied immediately, ‘Your throne, O God, is forever and ever,’ explaining, ‘These are praises to the Almighty.’ I then asked him to read the rest of the psalm, clearly addressed to the king, and his face dropped. How could this earthly king be called ‘elohim? To repeat: This is the most natural and obvious meaning of the Hebrew, and no one would have questioned such a rendering had the entire psalm been addressed to God.[7]

Of course, this title in Psalm 45 is referring to the Davidic king, but Jesus was the son of David (Mt. 1:1) who would fulfill the covenant given to his father David (2 Sam. 7:11-16).

Isaiah 48:12-16

(Isa. 48:12-13) Listen to Me, O Jacob, even Israel whom I called; I am He, I am the first, I am also the last. ¹³ Surely My hand founded the earth, and My right hand spread out the heavens; when I call to them, they stand together.

Of course, “the first and the last” refers to Yahweh (c.f. Isa. 41:4), who is the Creator of the Earth (Isa. 42:5).

(Isa. 48:14-16) Assemble, all of you, and listen! Who among them has declared these things? The LORD loves him; he shall carry out His good pleasure on Babylon, and His arm shall be against the Chaldeans. ¹⁵ I, even I, have spoken; indeed I have called him, I have brought him, and He will make his ways successful. ¹⁶ Come near to Me, listen to this: From the first I have not spoken in secret, from the time it took place, I was there. And now the Lord GOD has sent Me, and His Spirit.

Here, the speaker (Yahweh) says that Yahweh sent him! (vs. 16b) Therefore, unless the speaker in vs. 16b is a new speaker (as some assert), there are at least two persons who are called Yahweh. This passage does not prove the Spirit is God; it simply suggests that there are at least two persons who are both Yahweh.

Isaiah 61:1-2, 8

(Isa. 61:1-2) The Spirit of the Lord GOD is upon me, Because the LORD has anointed me to bring good news to the afflicted; He has sent me to bind up the brokenhearted, to proclaim liberty to captives and freedom to prisoners; ² to proclaim the favorable year of the LORD and the day of vengeance of our God; to comfort all who mourn.

Careful readers will notice that Jesus quoted this verse in Luke 4. He claimed that he was the one who was anointed by Yahweh.

(Isa. 61:8) For I, the LORD, love justice, I hate robbery in the burnt offering; And I will faithfully give them their recompense and make an everlasting covenant with them.

In verse 8, we see that the same speaker (as verses 1 and 2) refers to himself as the LORD.

Joshua 5:13-15

(Josh. 5:13-15) Now it came about when Joshua was by Jericho, that he lifted up his eyes and looked, and behold, a man was standing opposite him with his sword drawn in his hand, and Joshua went to him and said to him, “Are you for us or for our adversaries?” ¹⁴ He said, “No; rather I indeed come now as captain of the host of the LORD.” And Joshua fell on his face to the earth, and bowed down, and said to him, “What has my lord to say to his servant?” ¹⁵ The captain of the LORD’S host said to Joshua, “Remove your sandals from your feet, for the place where you are standing is holy.” And Joshua did so.

This is the language of Exodus 3:5 (“Do not come near here; remove your sandals from your feet, for the place on which you are standing is holy ground”). We should not worship angels (Col. 2:18; Rev. 19:10; 22:8-9) or humans (Acts 10:26; Mt. 4:10). However, Joshua falls down and worships the captain of the Lord’s host. Throughout the OT, God appears in the form of a man (Gen. 12:7; 17:1; 18:1) or an angel (Gen. 16:7-13; 48:15-16; Ex. 3:2-6). In one instance, the angel of the Lord is said to forgive sins (Ex. 23:21), and yet, we know that only God can forgive sins (Mk. 2:7). Therefore, the angel of the Lord must be a manifestation of Yahweh himself. Some theologians speculate that this is a pre-incarnate Jesus Christ. Of course, this does not mean that God is an angel, any more than God is a man, just because he came in the form of one (Phil. 2:7). Since the word “angel” just means “messenger,” we should differentiate the actions of an angel from the nature of one.

OBJECTION #4: “The doctrine of the Trinity was invented at the Council of Nicea in AD 325.”

The doctrine of the Trinity was clearly enunciated at the Council of Nicea, but it wasn’t created there. Moreover, the early church fathers did understand the deity of Christ.[8]

Justin Martyr (AD 150): “The Father of the universe has a Son, who also being the first begotten Word of God, is even God (First Apology, ch.63). “Whence to God alone we render worship” (First Apology, ch.17). “But both Him, and the Son (who came forth from Him and taught us these things, and the host of the other good angels who follow and are made like to Him), and the prophetic Spirit, we worship and adore” (First Apology, ch.6) “Therefore these words testify explicitly that He [Christ] is witnessed to by Him who established these things, as deserving to be worshipped, as God and as Christ” (Dialogue with Trypho, ch.63).

Tatian (AD 170): “We are not playing the fool, you Greeks, nor do we talk nonsense, when we report that God was born in the form of a man” (Address to the Greek, 21).

Melito of Sardis (AD 170): “Being God and likewise perfect man, he gave positive indications of his two natures: of his deity, by the miracles during the three years following after his baptism, of his humanity, in the thirty years which came before his baptism, during which, by reason of his condition according to the flesh, he concealed the signs of his deity, although he was the true God existing before the ages” (Fragment in Anastasius of Sinai’s The Guide, 13).

Irenaeus (AD 180): “He indeed who made all things can alone, together with His Word, properly be termed God and Lord: but the things which have been made cannot have this term applied to them, neither should they justly assume that appellation which belongs to the Creator” (Against Heresies, Book III, ch. 8, section 3). “But the Son, eternally co-existing with the Father, from of old, yea, from the beginning, always reveals the Father to Angels” (Against Heresies, Book II, ch. 30, section 9). “Christ Jesus is our Lord, and God, and Savior, and King” (Against Heresies, Book I, ch. 10, section 1).

Clement of Alexandria (AD 180): “There was then, a Word importing an unbeginning eternity; as also the Word itself, that is, the Son of God, who being, by equality of substance, one with the Father, is eternal and uncreated” (Fragments, Part I, section III). “He that is truly most manifest Deity, He that is made equal to the Lord of the universe; because He was His Son” (Exhortations, ch.10). “I understand nothing else than the Holy Trinity to be meant; for the third is the Holy Spirit, and the Son is the second, by whom all things were made according to the will of the Father” (Stromata, Book V, ch.14).

Tertullian (AD 200): “All the Scriptures give clear proof of the Trinity, and it is from these that our principle is deduced…the distinction of the Trinity is quite clearly displayed” (Against Praxeas, ch.11). “Thus the connection of the Father in the Son, and of the Son in the Paraclete, produces three coherent Persons, who are yet distinct One from Another” (Against Praxeas, ch.25). “That there are two Gods and two Lords, however, is a statement which we will never allow to issue from our mouth” (Against Praxeas, 13:6).

Common Heretical Illustrations

Let’s consider many of the illustrations that Christians often use to describe the Trinity and weigh their accuracy.

ILLUSTRATION #1: “The Trinity is like water. Water can exist in a liquid form, ice form, or gas form. One substance can do three different things. In the same way, God can appear as the Father, the Son, or as the Holy Spirit.”

Though it is often used in Christian circles, this illustration is actually a heretical view of the Trinity. The water doesn’t exist in these three separate states at the same time. God, however, exists as three separate persons at the same time. This illustration is a form of Modalism, where God merely appears as three persons, but consists of only one person.

ILLUSTRATION #2: “The Trinity is like a triangle. It is one triangle, but it has three separate points.”

This is a good illustration for the Trinity. One triangle contains three points. The points are different from the shape. The triangle is one in shape, three in points. Similarly, God is one in nature, three in person.

ILLUSTRATION #3: “The Trinity is like a man, who can play three different roles in a play. For example, Eddie Murphy plays several characters in the same movie. In the same way, God acts as the Father, the Son, and the Holy Spirit, but these are all the same God.”

This is a heretical illustration. God is simultaneously three persons—not one person playing three different roles. Again, this is Modalism. The doctrine of the Trinity teaches that God is not appearing as the role of the Son. There really is the Son. Likewise, he is not appearing in the role of the Spirit. The Spirit is a distinctive person.

ILLUSTRATION #4: “The Trinity is similar to the mythical dog Cerberus from Greek mythology. In the ancient Greek legend, Cerberus was a three-headed dog that Hercules needed to kill. Cerberus was one dog, but he had three distinct heads. In the same way, one God exists as three separate persons.”

In ancient Greek mythology, Hercules had to capture a three headed dog, who guarded the gates of Hades. He had three brains and three distinct consciousnesses. Despite the three independent consciousnesses, Cerberus is still one dog—one physical property. If Spike bit Hercules on the leg, he might report, “Cerberus bit me on the leg” or he might report “Spike bit me on the leg.”

As bizarre as this analogy is (especially considering the fact that it comes from Pagan mythology!), it is a helpful illustration to explain the three-in-oneness of God in the Trinity. Cerberus is one dog in nature. Yet he has three persons in the one nature (e.g. perhaps named Rover, Bowser, and Spike). Of course, most critics of the Trinity—specifically Unitarian monotheists like Muslims, Jews, and Jehovah’s Witnesses—usually take offense to this illustration, because it compares God with a dog! For this reason, it is wise not to use this illustration to those who are already suspicious of the Trinity being polytheistic.

Importance of the Trinity

Why is the trinity important? While the doctrine of the trinity is difficult to comprehend or explain, the alternative (no Trinity) presents more serious problems for a number of reasons.

First, the doctrine of the trinity resolves the tension between God’s love and his self-existence. There was always love between the persons of the Godhead (Jn. 17:5, 24; Eph. 1:4). The doctrine of the Trinity explains how God can be eternal but not solitary or lonely. He has always had relationships and expressing love is central to his character.^[9] How can God be loving and personal without having relationships? Love needs a lover and a beloved. It needs a giver and a receiver. Without multiple persons in his eternal nature, God would need humans to express love. But God was not in some sort of cosmic loneliness before creation, needing other personal beings to love. He was fully self-sustained in his triune nature. This aspect of God’s aseity is unresolved in Unitarian monotheisms like Judaism, Islam, and the Jehovah’s Witnesses.

Second, the doctrine of the Trinity provides a basis for personal love relationships. Human love relationships are not a biological accident; they are a reflection of the very nature of God and ultimate reality. God is a community of love relationships, and we value them because we are made in his image. Why is solitary confinement one of the worst punishments we can imagine? It is because we were made to live in community with others. Why did God call us to love and serve him in community? This is because he himself is a community of persons, who love each other.

Third, the doctrine of the Trinity makes the incarnation and atonement possible. Without three separate persons, the Father would not be able to pour judgment out on the Son and the Son would not have been able to be the offering for sin. Grudem writes, “Justification by faith alone is threatened if we deny the full deity of the Son. This is seen today in the teaching of the Jehovah’s Witnesses, who do not believe in justification by faith alone.”[10] Our doctrine of God will necessarily affect our doctrine of salvation; the two hang or fall together. Thus we see that the doctrine of the Trinity is not merely an abstract theological concept. Instead, it lies at the heart of Christian faith and practice.

Further Reading

Books on the Trinity

White, James R. The Forgotten Trinity. Minneapolis, MN: Bethany House, 1998.

By his own admission, White’s book is more for the believer, than the non-believer. In chapters 1 through 3, he outlines the definition of the Trinity, and he explains that the Bible is inherently monotheistic. Then, in chapters 4 through 9, he offers an exegetical case for the deity of Christ. Chapter 10 gives a case for the deity and personality of the Holy Spirit. Chapters 11 and 12 offer a further explanation of the Trinity, defining it very particularly with strict definitions. Chapter 13 covers the early church fathers, and it cites their view of the Trinity. Chapter 14 is really a concluding chapter that emphasizes the practical importance of the Trinity. White’s book is well-done, and he keeps most of the technical material in the footnotes, so the newer student of Scripture won’t be bogged down. He also keeps the length of the book to 224 pages.

Bowman, Robert M. Why You Should Believe in the Trinity: An Answer to Jehovah’s Witnesses. Grand Rapids, MI: Baker Book House, 1989.

Bowman is an apologist with advanced degrees in theology. He specializes in working with cult groups. In this book, he gives a detailed defense of the Trinity from the early church fathers (chapter 3) and the Bible (chapters 4-10).

Augustine On the Trinity (Found here)

Though this is a very old work, Augustine’s writing on the Trinity is still superb. However, we would only suggest this for more advanced students.

Chapters on the Trinity

Erickson, Millard. Christian Theology. Second Edition. Grand Rapids, MI: Baker Book House. 1998. Chapter 16: “God’s Three-In-Oneness: The Trinity.”

Grudem, Wayne. Systematic Theology. Grand Rapids, MI. Zondervan Publishing House. 1994. Chapter 14: “God in Three Persons: The Trinity.”

We prefer Erickson’s Christian Theology to just about any other on the market. He is fair and balanced in his assessment of contrary views. However, we felt that his chapter on the Trinity wasn’t as strong as Grudem’s, who handled the subject better. Grudem’s three pronged argument for the doctrine was helpful in thinking through the issue, and was very influential on the structure of this article.

Moreland, J.P. & Craig, William Lane. Philosophical Foundations for a Christian Worldview. Downers Grove, Illinois: IVP Academic. 2003. Chapter 29: “Christian Doctrines (1): The Trinity.”

Copan, Paul, and William Lane Craig. Contending with Christianity’s Critics: Answering New Atheists & Other Objectors. Nashville: B & H Academic, 2009. Chapter 14: “Is the Trinity a Logical Blunder?”

Whereas Erickson and Grudem focus on the biblical and theological aspects of the Trinity, Copan, Craig, and Moreland tackle the philosophical issues. This isn’t to say that these authors don’t overlap in their disciplines, but their focus or emphasis isn’t the same. If you’re looking for a philosophical treatment, consider these two chapters listed above.

[1] Against Praxeas, 2.4. Dunn wonders if Tertullian was really the first to use this term. He writes that later authors at the very least attribute it to Tertullian’s influence. Moreover, we may be reading our definition of the Trinity back into his use of this word (because of the enunciation of this doctrine at later councils). Geoffrey Dunn, Tertullian (New York, NY: Taylor and Francis Group. 2004), 7, 25.

[2] Millard Erickson, Christian Theology (Second Edition. Grand Rapids, MI: Baker Book House. 1998), 367.

[3] Grudem writes, “Some of the leaders who formed this group had earlier been forced out of the Assemblies of God when the Assemblies decided to insist on a trinitarian statement of faith for its ministers in 1916. The United Pentecostal Church is sometimes identified with the slogan “Jesus only,” and it insists that people should be baptized in the name of Jesus, not in the name of the Father, Son, and Holy Spirit. Because of its denial of the three distinct persons in God, the denomination should not be considered to be evangelical, and it is doubtful whether it should be considered genuinely Christian at all.” Wayne Grudem, Systematic Theology (Grand Rapids, MI. Zondervan Publishing House, 1994), 261.

[4] Modalists sometimes claim that the Holy Spirit really isn’t a distinct personal being; instead, it is just the “force” or the “will” of God. However, we see that the Holy Spirit contains personal qualities. He knows God’s thoughts (1 Cor. 2:11), distributes gifts (1 Cor. 12:11), prohibits ministry initiatives (Acts 16:6-7), and speaks to people (Acts 8:29; 13:2). Only personal beings can do such things. Theologian Wayne Grudem adds, “Then there are places where the masculine pronoun he (Gk. ekeinos) is applied to the Holy Spirit (John 14:26; 15:26; 16:13–14), which one would not expect from the rules of Greek grammar, for the word “spirit” (Gk. pneuma) is neuter, not masculine, and would ordinarily be referred to with the neuter pronoun ekeino. Moreover, the name counselor or comforter (Gk. paraklētos) is a term commonly used to speak of a person who helps or gives comfort or counsel to another person or persons, but is used of the Holy Spirit in John’s gospel (14:16, 26; 15:26; 16:7).” Wayne Grudem, Systematic Theology (Grand Rapids, MI. Zondervan Publishing House, 1994), 232.

[5] Wayne Grudem, Systematic Theology (Grand Rapids, MI. Zondervan Publishing House, 1994), 248.

[6] In the New American Standard Bible, when the words “LORD” or “GOD” are in all caps, the Hebrew word being used is YAHWEH (YHWH). YHWH refers exclusively to God. The terms “Adonai” and “Elohim,” are also used to refer to God, but can refer to other persons—their meaning is determined by the context.

[7] Michael Brown, Answering Jewish Objections to Jesus: Theological Objections. Volume 2. (Grand Rapids, MI: Baker, 2003), 43.

[8] These excerpts were generously taken from bible.ca “Earliest Christians taught Trinity!” See also Robert M. Bowman, Why You Should Believe in the Trinity: An Answer to Jehovah’s Witnesses (Grand Rapids, MI: Baker Book House, 1989), Chapter Three “The Church and the Trinity.”

[9] Francis Schaeffer writes, “Often in a discussion someone will say, “Didn’t God, then, if He is personal and if He loves, need an object for His love? Didn’t He have to create? And therefore, isn’t the universe just as necessary to Him as He is to the universe?” But the answer is, No. He did not have to create something face-to-face with Himself in order to love, because there already was the Trinity. God could create by a free act of the will because before creation there was the Father who loved the Son and there was also the Holy Spirit to love and be loved. In other words, God had someone face-to-face with Himself in the three Persons of the Trinity.” Francis A. Schaeffer, Genesis in Space and Time (Downers Grove, IL: Inter-Varsity, 1972), 26

[10] Wayne Grudem, Systematic Theology (Grand Rapids, MI. Zondervan Publishing House, 1994), 247.