The Importance of Defending the Trinity

Founders Journal · Winter 2003 · pp. 18-20

The Importance of Defending the Trinity

Gannon Murphy

One of the first clues that tip off the seminal importance of the historic doctrine of the Trinity is the perennial smoke of controversy that has surrounded it throughout the history of the church. Antitrinitarianism is a positively ancient cancer that has festered and re-festered in a multitude of forms over the last two millennia. Indeed, the seemingly endless demand for a cogent and sturdy defense of biblical Trinitarianism provided many of the church fathers with the motivation they needed to pen some of the most powerful apologetical works ever issued. Tertullian’s, Against Praxeas (second century), Gregory of Nyssa’s, On Not Three Gods (fourth century), and Augustine’s, On the Holy Trinity (early fifth century) are just a few examples of works defending the Trinity. The Trinity was also the central issue at several early church councils such as those in Nicea (325) and Constantinople (382) where the heretical, antitrinitarian teachings of Arius and his followers were sternly repudiated. Significant spurts of antitrinitarianism continued, however, and carried themselves well over into the Middle Ages (especially in Peter Abelard and the Nominalists), through the period of the Reformation (as in Faustus Socinus and his followers, the Socinians), and well into the period of the Enlightenment in which antitrinitarian congregations began sprouting up all over Europe and were carrying over to America.[1] Indeed, a steady stream of vehement antitrinitarianism can be traced all the way through the first century right up to the present day where it is made brazenly manifest in such groups as the Unitarians, Mormons, Christian Scientists, Theosophical Society, and the Jehovah’s Witnesses.

The doctrine of the Trinity is consistently among the first of those teachings to be banefully attacked by the opponents of the historic, Christian faith. Cultists and religious devotees of multitudinous persuasions come against Trinitarianism with a venom uncommon in most other arenas of doctrinal controversy. Missionaries for the Mormon church, Jehovah’s Witnesses, and Islam, for example, often receive training in specific methods targeted at “refuting” the Trinity.

Why is this? Why all the hubbub? What is so threatening about a doctrine which some would care to deem merely “academic,” “heady,” “too speculative,” “contradictory” or “confusing”? The answer is really quite simple: If the Christian doctrine of the Trinity is not true, then Jesus Christ is not Who He said He was, namely, God the Savior. But if it is true, resistless logic points to the inescapable conclusion that Jesus Christ is indeed, the logos sarx, the Word in human flesh Who “made His dwelling among us” (John 1:14). Enemies of the Holy Trinity know that if the fabric of Trinitarianism can be torn down, then Jesus was but a mere man, perhaps a prophet at best, but certainly not the Theanthropos, the Godman–100 percent man, 100 percent Deity (Philippians 2:5-7) as the Bible and the historic creeds of Christendom affirm. And if Christ was not these things, then He did not render sufficient satisfaction for our sins by virtue of His death and on the cross and victorious resurrection three days later. Indeed, as Paul affirms, “if Christ has not been raised, your faith is futile; you are still in your sins” (1 Corinthians 15:17). If the Trinity is not true, then Christ is not God the Son resurrected and, plain and simple, Christians worldwide are worshipping a dead man. So how important is the Trinity and its defense? I’d say it doesn’t get more important than this!

The Bible, of course, never actually uses the word “Trinity.” Rather, the term–since coined by Tertullian in the second century–“has simply been found a convenient designation for the one God self-revealed in Scripture as Father, Son, and Holy Spirit.”[2]Biblical passages affirming both the “Oneness” and the Triunity of this Oneness are in ample supply. Deuteronomy 6:4 affirms that “The Lord our God is one Lord” while passages such as Matthew 28:19 and 2Corinthians 13:14 both make explicit use of the “Trinitarian formula.”[3] The divinity of Christ is also affirmed in various places like Colossians 2:9 where Paul calls Jesus “the one in whom the fullness of deity dwells bodily” (see also Philippians 2:5-7; John 8:58, 17:5; Revelation 2:8).

Contrary to the claims of skeptics and antitrinitarians, the doctrine of the Trinity does not go against reason, but rather beyond it.[4] There is an unbridgeable difference between these two assertions. The Trinity is a mystery, not a contradiction. Properly formulated, the doctrine declares that “God is one in nature (or essence) and three in person” thus doing no violence to reason. If, on the other hand, the doctrine were to declare that God is “one in nature and three in nature,” then, indeed, we would have an irreconcilable contradiction. For, in this case God is said to be both one and three at the same time and in the same sense which is a patent violation of the law of noncontradiction which governs all rational thought and without which all intelligible discourse would be impossible. That the Trinity is logically tenable does not, however, alter its status as an intractable theological mystery. How the three Persons of the Trinity co-inhere one another in the Divine perichoresis, though noncontradictory, is beyond the human capacity to understand. Finitum non capax infinitum, the finite cannot contain the infinite.

The doctrine of the Trinity cuts right to the core of the very constituent nature of God. For this reason, the doctrine is an essential teaching of the Christian faith with salvific import. For, as we have seen, it is inextricably interwoven with Who Christ is–the Author and Perfecter of our faith (Hebrews 12:2). To reject the Trinity is to reject the God Who Is.

We should not agonize over the mysteriousness or complexity of this doctrine. Rather, we should take great comfort in it. For, a most glorious aspect of the Trinity is the manner in which it represents the eternal relationality of God, in perfect love. St. Augustine spoke at length of this Tri-unity of love. Love, he said, involves a lover. Thus, the Father might be likened to the Lover; the Son to the One loved, and the Holy Spirit to the bond of love.[5] C. S. Lewis once put it this way, “The union between the Father and the Son is such a live concrete thing that this union itself is also a Person.”[6]The Trinity, then, makes the very fact of love possible–an important and comforting fact indeed. When a person becomes a Christian, that person enters in to the Triune love. Some theologians, including a professor I once had in seminary, sometimes even refer to God’s saving work (as well as the entire panoply of redemptive history) as “the Trinification of the world.”[7]

The prodigious energies that the great apologists of Christian orthodoxy throughout the centuries have poured into defending the historic doctrine of the Trinity should humble the pervasive laxity and docility of the church today with regard to this cardinal tenet of the faith. It is not simply a “heady speculation” or “abstract doctrine” without real, live import for our lives. The Trinity grounds our salvation in the immutable reality of the Godhead. It is not on optional or marginal teaching. The Christian faith is not such that we can pick and choose our doctrines and affirm one central tenet while we drop another. Where the essentials of the faith are concerned, you cannot say, “Hey, at least I’ve got 9 out 10!” Its an all or nothing deal. St. Augustine says, “In essentials unity, in non-essentials liberty, in all things charity.” The doctrine of the Trinity falls into the first category. This is not a debate over end-times scenarios, modes of baptismal administration, old earth vs. young earth, or similar in-house issues which we should debate with vigor but not divide over. Rather, the Trinity is a doctrinal hill that all Bible-believing Christians must be willing to die on and to defend with the utmost of fortitude. Paul says, “Watch your life and doctrine closely…” Why? Paul says, “…because if you do, you will save both yourself and your hearers.” This is a matter of eternal salvation and is precisely why we must not be lax toward it but must be ready to offer a defense–in an age where it is unpopular to do so–of the paramount importance and centrality of the Trinity.


1 C. G. Singer, “Unitarianism” Evangelical Dictionary of Theology (Grand Rapids, MI: Baker Books, 1984), 1126.

2 G. W. Bromiley, “Trinity” Evangelical Dictionary of Theology (Grand Rapids, MI: Baker Books, 1984), 1112

3 Herbert Lockyer (Editor) “Trinity” Illustrated Dictionary of the Bible (Nashville, TN: Thomas Nelson Publishers, 1986), 1073.

4 Norman Geisler, “Trinity” Baker Encyclopedia of Christian Apologetics (Grand Rapids, MI: Baker Books, 1999), 730

5 Ibid., 733

6 C. S. Lewis, “The Trinity” The Joyful Christian (New York, NY: Simon and Schuster, 1977), 47

7 James Beilby, Lecture on the Doctrine of God, Bethel Theological Seminary (October 2000).