What is the Doctrine of the Trinity?


What is the correct understanding of God's person as portrayed in Scripture and what bearing does this have on the Christian life? Some argue for a centrality in the person of God, which He manifests in different modes while denying a distinction in persons. Others argue for a singularity in the person of God, which leads to a denial of the divinity of the Son. The biblical evidence, however, shows that God is one, and He exists in the persons of Father, Son, and Holy Spirit. This understanding of God's tri-unity not only teaches Christians how God relates in Himself, but also how they are to relate to Him, and how they are to relate to each other. By examining the foundational tenants of Arianism and Modalism and their primary points of contention with Nicene Trinitarianism, this blog will offer a retort to these arguments by consulting a myriad of relevant biblical texts as well as presenting the works of both historical and current scholars who have engaged in this field of study.

Tracing an understanding of the Doctrine of the Trinity through the annals of church history will demonstrate the primacy of this doctrine in the forefront of the debates on Christian orthodoxy. Reprehensibly, this trail of formulation is one marked in blood. Orthodox or otherwise, some so convinced of their understanding of God’s personal composition were willing to lose their lives for it. Such a sacrifice begs the question: why does the Doctrine of the Trinity carry with it such weight in the spectrum of Christian doctrines?

In the opening line of his magnum opus, John Calvin writes, “Our wisdom, in so far as it ought to be deemed true and solid wisdom, consists almost entirely of two parts: the knowledge of God and of ourselves.”[1] Calvin rightly concludes that a proper understanding of God begets a proper understanding of self. In addition, a proper understanding of God begets a proper understanding of the purpose of humanity’s existence, how they are to relate to one another, and, ultimately, God’s disposition toward them, making the Doctrine of the Trinity the most important doctrine of the Christian faith. For, “to study the Bible’s teachings on the Trinity gives us great insight into the question that is at the center of all of our seeking after God: What is God like in himself?”[2]


Because the Nicence formulation of the Trinity, one God who exists eternally in the three co-equal persons of Father, Son, and Holy Spirit, carries with it a great deal of mystery, some sought to implement an Occam's Razor approach to arriving at a biblical understanding of the Person of God. Since God is not a God of confusion (1 Cor 14:33), it stands to reason that the least mysterious and most easily comprehended concept of the Person of God should be understood through a Modalistic understanding of God. This understanding posits that the three persons of God are simply three ways (modes) in which one God has revealed Himself.[3] This view denies any notion of a plurality in persons, and any view which believes thusly not only creates a division in the Godhead but violates that which God has expressly declared Himself to be: One (Deut 6:4; Gal 3:20).

Using Scripture as the foundational base of formulation, Modalists find no biblical references to the terms Trinity or Same Substance (homoousios). While they concede references to ostensible names of God’s persons (Father, Son, and Holy Spirit), they maintain these to be merely titles determining roles that the indivisible Godhead plays. The Modalist holds that:

God revealed himself successively in salvation history, first as Father (creator and lawgiver), then as Son (redeemer), and finally as Spirit (sustainer and giver of grace). For a modalist, the God of the Old Testament is the Father. In the incarnation, God was manifested in Jesus. Then, after the resurrection and ascension of Christ, God came in the mode of the Holy Spirit.[4]

As an actor changes masks to indicate a change in character, so God manifests Himself as Father in the Old Testament, as Son in the Gospels, and as Holy Spirit in the age of the church. And like an actor, "when the part was played, the character would disappear until or unless required again."[5]

One author suggests that while the word "modalism" may be foreign to most Christians, this understanding is the most commonly accepted theological understanding of the nature of God's being among people who consider themselves to be Trinitarian.[6] When a pastor explains to his church that the Trinity is like a bucket of water that can appear as ice, liquid, or steam, he is actually teaching them Modalism since none of these states can exist simultaneously.

Unlike Arianism, which seeks to maintain God’s singularity of person by denying the full deity of Christ, Modalism “stresses the full deity of Christ and thus does justice to the tremendous impact he made upon his age, and it avoids the suggestion that he is a second God alongside the Father."[7] Modalists, however, argue against an understanding of three distinct centers of consciousness in the Godhead or the notion that Jesus is one of three divine persons.[8] Against this, some argue that there are a great deal of passages that deal with Jesus speaking to the Father as distinct from Himself, or the fact that Jesus promises another comforter (Spirit). To this the Modalist would retort: like all doctrinal formulations on the nature of God's being one must end with some sense of mystery. Praxeas, an early second century Modalist, argued that “God is God, and for Him all things are possible.”[9] Because of this, God is free to reveal Himself in any mode He should choose. Any attempt to delve into how God, who is in and of Himself ineffable, does anything, is to peer behind the curtain of the secret things that belong to the Lord alone (Deut 29:29).


Others, like Arius, the third-century presbyter of Alexandria, are determined to monomaniacally defend the singularity of God’s being against any who claim God to be other than He presents Himself to be in the Bible. For Arius, when God says He is one, He means just that. Since God is one, Jesus could not have simultaneously shared God’s true divinity. Therefore, an incarnational understanding of the Son is heretical. Arius taught that the Father alone was the true God, “inaccessible and unique in being arkhe, the principle of all beings, the Logos [Jesus] being neither coeternal with him, nor uncreated, because he received life and being from the Father."[10] Arianism denies the full deity of the Son, and by muting the second Person of the Trinitarian formula, subsequently eradicates the third as well.

The Gospel of John states that God, wanting to make His love for the world known, sent His begotten Son to die for it (John 3:16). From the vantage point of the Arian, the blaring question is this: If God is eternal, and if the Son is God, how is it that He is begotten? Arius argued:

The Son was not always; for since all things have come into existence from nothing, and all things are creatures and have been made, so also the Logos of God himself came into existence from nothing and there was a time when he was not; and before He came into existence He was not; but He also had a beginning of His being created.[11]

Arius’ bishop, Alexander, would contend: "’God is always, the Son is always' and that the Son 'is the unbegotten begotten'.”[12] In contrast to this, Arius believed the Son, though the eldest and highest of creatures, had a beginning, whereas God is from everlasting to everlasting.

Arius affirmed the Word to be both unique in perfection and divinity, albeit still created. Because of this distinction, Arius could truthfully confess: "Christ was God, because the Father willed him to be so, but he was not God necessarily and essentially."[13] The distinction, however, must be made between full and imbued divinity. Arianism argues:

Though the Son is a heavenly being who existed before the rest of creation and who is far greater than all the rest of creation, he is still not equal to the Father in all his attributes—he may even be said to be “like the Father” or “similar to the Father” in his nature, but he cannot be said to be “of the same nature” as the Father.[14]

Hence, Arianism denies a full divinity of Christ and affirms an imbued divinity.

Although Arius receives a great deal of derogatory criticism, as far as history indicates, he was finicky and careful in his study of the Bible. Arianism views the incarnational understanding of the Son, which claims Jesus was God in the flesh and died on the cross, to be blasphemous. Scripture, in fact, extinguishes this as a possibility, for God is one (Deut 6:4), He does not change (Mal 3:6), He is not a man (Num 23:19), and He is eternal (Gen 21:33). Using Sola Scriptura as the rule of faith, Arianism makes its case by utilizing the law of non-contradiction. If God is one, how does He share His divinity without violating His singularity in person? If God is immutable, how does He become man, that which He has expressly described Himself as not being? Lastly, if God is eternal, how does He beget Himself, taking the form of a man and then die on a cross? Therefore, in order to maintain God’s singularity in person, and to deal with the biblical testimony of Christ’s exalted status, Arianism presents Jesus to be the highest created being of God.[15]


The Bible stands as God’s supremely inspired disclosure of self, and it is in the Bible that God reveals Himself to be a Trinitarian God. In it God is shown to be one being, of one essence, who exists in three, coequal, coeternal persons: Father, Son, and Holy Spirit. God has revealed Himself as such for the good of the believer, making the study of the Trinity of upmost priority for the Christian. To further one’s understanding of the Trinity, insomuch as finite minds can grasp the infinite, is to grow in one’s knowledge of God. The doctrine of the Trinity is the core foundation on which the Christian faith is built. The consequences for diluting the significance of a right understanding of God are dire. Bruce Ware gives this critical warning to anyone who wishes to degrade the importance of the Trinity: “Remove the Trinity, and the whole Christian faith disintegrates.”[16]

While the term 'Trinity' cannot be found in Scripture, “Christian theology has used it to designate the threefold manifestation of the one God as Father, Son, and Holy Spirit.”[17] Using artificial terms like ‘Trinity’ assists the Christian to verbalize the truth about God as He has disclosed Himself in Scripture. The Trinity, then, is an understanding of God’s singularity in essence and plurality in persons. This truth is interwoven throughout the Old and New Testaments, for the Scriptures declare God as one (Deuteronomy 6:4; James 2:19), yet the Son (Isaiah 7:14; John 1:1) and the Spirit (Job 33:4; 1 Cor 3:16) are fully God.

To better understand God’s true nature as He exists in Himself, one should focus on God’s self appropriated descriptions. One such instance is Jeremiah 2:13, where God refers to Himself as a fountain. In the same way that a fountain pours water, so the Father, from eternity past, has love that cascades from His person into His eternal Son (John 17:24). From before the foundations of the world were laid, the Father has loved the Son, and it is from this eternal love that theologians conclude: “[The Father] finds his very identity, his Fatherhood, in loving and giving out his life and being to the Son.”[18] Since God is eternally the Father, there cannot have been a time when the Son did not exist, for such would require a time when the Father ceased to be Father. The Father declares and demonstrates His love for His Son by anointing His Son with the Holy Spirit (Matt 3:16). At the Baptism of Jesus, the Father sends the Spirit to rest on the Son, effectively declaring to the world, “This is my Son, whom I love” (Matt 3:17).

Though each person in the Trinity is of the same substance and shares the same attributes, there is a functional, though unnecessary, hierarchical arrangement of authority in the Godhead. One cannot, however, observe aspects of the nature of God “as that which distinguishes the Father from the Son or Spirit.”[19]Rather, in order to observe distinctions in the Trinity, one must carefully inspect the roles and relationships that set apart the Father in relation to the Son and the Spirit. For the Father, who eternally loved the Son (John 17:24), sent His Son (John 6:4) to die for the sins of the world (John 3:16). This Son did nothing but obey the Father’s command and submit to His will (John 5:19). Though the preincarnate Son had authority over the Spirit, by coming in the flesh the Son humbled Himself by becoming obedient to the Spirit (Phil 2:8). By living in full reliance on the power of the eternal Spirit (Hebrews 9:14), the Son was able to fully keep the law, all to the glory of the Father (John 17:4). In the same way that the Son was sent out by the Father and did not speak on His own authority but came only to glorify the Father, so the Spirit is sent by the Father and the Son (John 15:6) to glorify the Son and declare His teaching to the church (John 16:14). This economy of the Trinity is most readily seen in the sending of the Spirit:

The Father, as ultimate in authority over the Son and the Spirit, calls the Son forth from the grave and sets him at his own right hand. Then the Father, rather than giving the Spirit directly to the church, instead gives the gift of the Spirit to his Son so that the Son might have the honor and privilege to give the Spirit, from the Father, to those redeemed and called to new life through his work on their behalf. So the Son, having received this gift of the Spirit from the Father, then passes on this gift to the believers on the day of Pentecost.[20]

Therefore, every blessing comes from the Father, through the work of the Son, mediated by the Spirit.

Not only is a proper understanding of the Trinity necessary to know who God is as He relates to Himself, but a robust understanding of the Trinity is necessary to comprehend how salvation works. For salvation comes as the Father judges the sin of the world in his Son, who came in the flesh and lived in full reliance on the empowering of the Holy Spirit as the perfect and sinless God-man, effectively exemplifying perfect obedience to the Father by the anointing of the Spirit. The Son obeyed the will of the Father, which was death on a cross, in order to reconcile the elect to Himself and reverse the effects of the curse. Since humanity has no access to God because of sin, Christ, the High Priest, stands as mediator between God and men to reconcile them to the Father. In Christ's death there is forgiveness of sins. In His resurrection, by His Spirit, there is newness of life. The Spirit, then, glorifies the Son by illuminating believers and revealing the depths of the Son, thereby transforming them to His image. It is in this image that the Father loves the Christian, for when He sees them He no longer sees their sin, but His Son, whom He has loved from eternity past. To disregard the Trinity is purposely to undermine salvation.[21]

God reveals Himself as Father, Son, and Spirit, not to confuse His people but for their good. For without an orthodox and rich understanding of God’s tri-unity, one’s time in prayer is almost certainly dissonant babble. When the disciples asked Jesus to teach them how to pray, He instructed them to pray, “Our Father” (Matthew 6:9). To call on God as Father is to intimate a close personal relationship with Him. How, then, can one come to call on God as Father? Only those who are united with Christ receive a Spirit of adoption (Romans 8:17), and by the efficacious work of the Son on the cross, they can, by the Spirit, call out to God as Father. A right understanding of the Trinity invigorates the prayer life of Christians when they learn to “acknowledge the roles of Father, Son, and Spirit as we pray to the Father, through the Son, in the power of the Spirit.”[22]


The Modalists were so concerned with avoiding polytheistic heresies that they emphasized the singularity of God’s essence to the detriment of His persons, believing that the three persons of God are simply three ways (modes) in which God has revealed Himself. This understanding of the personhood of God is still very prevalent among much of the modern charismatic movement. The Modalists depict God as a caricature: an actor with three different masks. They take the three distinct persons of the Godhead and turn God into a purée of persons. As one author writes, “The trouble is, once you purée the persons, it becomes impossible to taste their gospel.”[23] The author goes on to explain, when one diminishes the Sonship of Christ and makes Him merely a mode, then there is no Son with whom believers are to be united. Additionally, if there is no distinct eternal Father, then Christians can never truly be called the children of God.  A Modalist, then, is left with a God with a personality disorder as, “Somehow the Son must be his own Father, send himself, love himself, pray to himself, seat himself at his own right hand and so on.”[24]

The Modalists have a great deal of explaining to do as there are explicit passages which showcase all three persons functioning simultaneously. In Genesis 1:1, the Father creates through His Word, while the Spirit was hovering over the water (Genesis 1:2). In Genesis 1:26-28, God speaks with one voice in a plurality of persons by saying, “Let us make man...”Again, after the fall of man, God declares, “Behold, the man has become like one of us...” (Genesis 3:22, emphasis mine). In Genesis 11:7, God, who is in heaven, announces, “Come, let us go down there...” From just the first book of the Bible there are references to a plurality of persons functioning simultaneously, thereby excluding the possibility of interchangeable modes.

Arius, on the other hand, believed that God’s oneness was predicated on not sharing His attributes with another. What makes God God, in his mind, was that there are none like Him. To suggest that Christ, the begotten, was God, the begetter, is to commit blasphemy of the highest sort. From his vantage point, God cannot share His divinity without violating His singularity in person; therefore, Arius concluded that Jesus was not equal to God, but was God’s highest created being. Using passages such as Mark 13:32, where Jesus concedes that no one but the Father knows when the Son will return, Arius launched his assault on the deity of Christ.

Although Arius believed his argument to be founded on Scripture, he came to the text with a presupposition that Jesus could not have been God. Sadly, Arius, and many since, have been blinded by this lie. Since the Holy Spirit longs to glorify the Son, the Spirit inspired the Bible (2 Timothy 3:16-17) to attest not only to the teachings and works of the Son, but also to bear testimony to the identity of the Son. In the New Testament, Jesus is repeatedly declared to be God by both others (John 1:1–4, 14; 5:17–18; 8:58; 10:30–38; 12:37–41) and Himself (John 5:17–23; 8:58–59; 10:30–39; 19:7).

Arius’ argument against the deity of Christ cannot hold its ground against the barrage of texts that speak otherwise. In Colossians 1:15-16, Jesus is said to be the image of God and creator of all things. In Philippians 2:9-12, Paul writes that every knee will bow to Jesus and confess Him as Lord. In Mark 2:5, Jesus forgives a man’s sins. In John 17:22, Jesus speaks of the Father giving Him glory; the God who does not share His glory with anyone (Isaiah 42:8) is said to have given it to His Son. In John 8:58, Jesus refers to Himself as “I am,” thereby claiming to be none other than Yahweh of the Old Testament, the God whose name eternally is “I am.”[25] While this list is in no way exhaustive, from just this small sample of passages one can see that Jesus created everything, will be worshipped as Lord, forgives sin, shares the glory of the Father, and calls Himself by God’s covenant name. The best hermeneutic is one that allows Scripture to interpret Scripture. With that, Arius was incalculably wrong. Not only this, but John was clear who would deny the deity of Christ: “Who is the liar but he who denies that Jesus is the Christ? This is the antichrist, he who denies the Father and the Son” (1 John 2:22).


An orthodox understanding of the Trinity, then, is one that affirms that the Father, Son, and Holy Spirit are fully God. Each person in the triune Godhead possesses the same divine nature equally, denouncing Arianism. Additionally, each person exists simultaneously, denouncing modalism.[26] Developing a robust Trinitarian knowledge helps Christians to understand how God relates in Himself, who they are in relation to Him, and how they ought to relate with each other.

[1]John Calvin, Calvin: Institutes of the Christian Religion, ed. John T. Mcneill, trans. Ford Lewis Battles, Paperback (Louisville: Westminster John Knox Press, 2011), 1:35.

[2]Wayne Grudem, Systematic Theology: An Introduction to Biblical Doctrine (Grand Rapids: Zondervan, 2009), 226, Kindle.

[3]Gregg Allison, Historical Theology: An Introduction to Christian Doctrine (Grand Rapids: Zondervan, 2011), 235-36,  Kindle.

[4]Mark Driscoll and Gerry Breshears, Doctrine: What Christians Should Believe (Chicago, IL: Crossway Books, 2010), 31, Kindle.

[5] David Christie-Murray, A History of Heresy (London: New English Library, 1976), 40.

[6]Harold O.J. Brown, Heresies: The Image of Christ in the Mirror of Heresy and Orthodoxy from the Apostles to the Present (Garden City, NY: Doubleday & Company, Inc., 1984), 99.


[8]“The Oneness of God,” United Pentecostal Church International, last modified May 24, accessed September 24, 2013, http://www.upci.org/about-us/beliefs/21-about-us/beliefs/91.

[9]Justo L. Gonzalez and Catherine Gunsalus Gonzalez, Heretics for Armchair Theologians (Louisville: Westminster John Knox Press, 2008), 81.

[10]Christie-Murray, A History of Heresy, 46.

[11] Athanasius, “Orations Against the Arians, Book I,” in The Trinitarian Controversy, trans. and ed. William G. Rusch (Philadelphia: Fortress Press, 1980), 67.

[12]Christie-Murray, A History of Heresy, 45.

[13]Ibid., emphasis mine.

[14]Grudem, Systematic Theology, 243.

[15]Mark Driscoll and Gerry Breshears, Doctrine, 32.

[16]Bruce Ware, Father, Son, and Holy Spirit: Relationships, Roles, and Relevance, Kindle ed. (Wheaton, IL: Good News Publishers, 2005), Kindle Location 139-40.

[17]R.L. Saucy, “The Trinity,” In Evangelical Dictionary of Theology, second edition. ed., Walter Elwell (Grand Rapids, MI: Baker Academic 2001), 502-3.

[18]Michael Reeves, Delighting in the Trinity: An Introduction to the Christian Faith, Kindle ed. (Downers Grove, IL: Intervarsity Press, 2012), 27.

[19]Ware, Father, Son, and Holy Spirit, Kindle Locations 567-69.

[20]Ibid., Kindle Locations 1349-52.

[21]Ibid., Kindle Locations 147-49.

[22]Ibid., Kindle Locations 161-62.

[23]Reeves, Delighting in the Trinity, 32-3.

[24] Ibid.

[25]Ware, Father, Son, and Holy Spirit, Kindle Locations 1277-81.

[26]Ibid., Kindle Locations 508-11.