Introduction to the Trinity

In Finding the Right Hills to Die On, Gavin Ortlund lays out a framework for ranking different doctrines to show which are necessary to debate and in which context to do so. In theological debates, “Some hills are worth dying on. If they are lost, everything is lost.” When it comes to those doctrines which are central to the Christian faith, “The denial of a first-rank doctrines is a vital loss.”(1) Fellow brothers and sisters in Christ may quibble over the Lord’s Supper or the Atonement. However, to speak to someone who believes that Jesus Christ is not God, is to speak to a non-Christian. To believe that the Son is a created being, is to side with Jehovah’s Witnesses. To believe the Father, the Son, and the Holy Spirit are separate gods is to be a polytheist, like the Mormons. The Trinity is so vital to Christians that to lose it is to lose God and the Gospel. This article will present a positive case for Classic Trinitarianism, define Trinitarian vocabulary, and examine historical anti-Trintiarian heresies to test understanding.

Divine Incomprehensibility

One problem in defining God is Divine Incomprehensibility. Humans, being finite, worship a God, “whose essence cannot be comprehended by any but Himself.”(2) Yet, God has revealed some of Himself to us. The way theology is studied must align with Deuteronomy 29:29, “The secret things belong to the Lord our God, but the things that are revealed belong to us and to our children forever, that we may do all the words of this law.”(3) God has set up divine guardrails for us. On one hand we can and must pursue God as He has revealed Himself; on the other, we cannot go further than we have Scriptural warrant to.

Unity of Essence

Twice a day for millenia, Jews of every generation have prayed the Shema to confess who God is. The Shema is taken from the book of Deuteronomy where God teaches His people to pray: “Hear, O Israel: The Lord our God, the Lord is one. You shall love the Lord your God with all your heart and with all your soul and with all your might.”(4) At the root of who God is, He is ultimately One. God’s unity of being is defined as Him having one essence (ouisas in Greek). R.C. Sproul writes of essence as, “The stuff that distinguishes a human being from an antelope… or a grape from God.” When we speak of God’s essence we are speaking of, “The stuff of deity, the essence–the ousias– is what God is in Himself. When the church declared that God is one essence, it was saying that God is not partly in one place and partly in another. God is only one being.” (5) Francis Turretin defines essence as the, “whatness (quidattium) of a thing.”(6) A thing’s essence is that without which the thing could not be. For example, a knife, though it may have a different shape, a different handle, or be crafted out of a different material, will still be a knife; however, the moment that the blade is removed from a knife, it cannot cut, and it ceases to be a knife. This concept of the Divine Essence, God being one, was so vital to Hebrew worship that God commanded Jews to teach the Shema, “when you sit in your house, and when you walk by the way, and when you lie down, and when you rise.” (7)

Divine Simplicity

The difficulty of fully grasping the Divine essence is that we often attempt to understand God as if He is a human. God is completely unique. God’s uniqueness is expressed as Divine Simplicity. God is without parts. Humans can still be called humans if they have a part (say, an arm or an eye) removed from them. God’s attributes are indistinguishable from His essence. To say “God is love” (8) is to say that you cannot remove His love from His essence, it is central to His very being. Through both the Shema and the definition of essence, we confess that, “We believe in one God, the Father almighty.”(9)

Eternal Relations of Origin

Why call the Father, the Father? The first reason is that it is what Jesus teaches us to do. He says in Matthew 6, “Pray then like this: Our Father in heaven, hallowed be your name.”(10) The second has to do with what is called the Eternal Relations of Origin, that is, how the three Persons of the Trinity relate to one another. The Father is called the Father, “because he begets his Son (paternity), though he himself is begotten by no one.” The Son is called the Son “because he is begotten by his Father (filiation.)” The Spirit is called the Spirit, “because he is breathed out by the Father and the Son (spiration.)” (11)

Distinguishing the Son

In the prologue of the Gospel of John, the Apostle John begins, reminiscent of the beginning of Genesis, “In the beginning was the Word.”(12) John ends the prologue by revealing the Word to be Jesus Christ. James White explains that the tense of the Greek word we translate as “was” expresses, “continuous action in the past,” leading to the conclusion, “as far back as you wish to push “the beginning,” the Word is already in existence. The Word does not come into existence in the “beginning,” but is already in existence when the beginning takes place.”(13) The Word is described as existing “in the beginning,” not that the Son was created at the beginning. Taken alone, this would indicate that there was a separate essence, the Word, that exists alongside God. To avoid this error, the Apostle John continues, “the Word was with God, and the Word was God.”(14) R.C. Sproul explains that when John uses this phrase, “John is indicating that the [Word] was in the closest possible relationship to God.”(15) This declaration, “is a clear ascription of deity to the Word. The Word is differentiated from God, but the Word is also identified with God.” (15) New vocabulary must be introduced to maintain God’s unity of essence, along with Jesus being in some way different, and yet being God. The term used to differentiate the Father from the Son, and the Son from the Spirit, has historically been “person,” from the Latin word “persona.” The term “person” raises difficulties as all humans, indeed all known creatures, have one person within their one essence. Whereas there are three Persons subsisting in the One essence of the Godhead. In place of person, the term “subsist” is used to clarify. Subsist, subsisting, or subsistence is defined by Turretin as a “mode of existing proper to substance.” \(16) Subsistence refers to how “the one essence of God ‘subsists’ or ‘exists’ in a unique way in each Person.”(17) The Father relates to the Son in that the Father is eternally begetting the Son, meaning “The persons are identical in all things except these personal properties.”(17) Or more succinctly, “The one, simple divine essence subsists or exists in three persons. Each person is a subsisting relation of the divine essence.”(18) Speaking of the divine essence subsisting in the Three Persons of the Trinity allows us to confess, “We worship one God in Trinity and the Trinity in unity, neither confounding their persons nor dividing the essence.”(18) Without cleaving the one divine essence into separate parts, we still worship “One Lord Jesus Christ, the only-begotten Son of God, begotten of the Father before all worlds; begotten, not made, being of one substance with the Father.” (9)

Co-Equality

Thus far, most of the conversation has been spent on distinguishing Jesus from the Father, but what about the Holy Spirit? How do we know that He is God, just as Jesus is? Much of the Gospels focus on the life and deity of the Son for one key reason. Jesus is an exceedingly controversial figure. Historically, the only notable group that focused on the denial of the deity of the Holy Spirit, as opposed to the deity of the Son, were the pneumatomachians [Spirit-Fighters.] To establish the Spirit’s deity we must see how He is described, such as His, “holiness (Matt. 12:32), eternality (Heb.9:14), omnipotence (Rom. 14:18-19), and omniscience (John 14:26).”(19) Given divine simplicity, for the Spirit to possess any of the attributes of the divine essence would be more than enough to prove His full subsistence in the divine essence. Understanding this, we confess, “The Father is Lord, the Son is Lord, the Holy Spirit is Lord. Yet there are not three lords but one Lord.” The Spirit is co-equal with the other Persons in the Godhead and here is “unity in Trinity, and Trinity in unity, which is to be worshiped.”(20) he Church believes in “the Holy Spirit, the Lord and Giver of life, who proceeds from the Father and the Son.” (9)

The Nicene Trinity, Conclusion

There are three primary pillars of orthodox Trinitarianism: God is one in essence, within the one essence of God there subsist three persons, the three persons are co-equal and co-eternal with one another. Having built the positive case for the Trinity we will now examine some of the most common historic Trinitarian errors.

Historical Errors

Sabellianism, also called Modalism, is the teaching that God exists in different modes of being. Sabellias taught that God is not three in Person, but exists in the mode of the Father in one instance, the mode of the Son in another, and the mode of the Spirit in a third. T he idea came from ancient plays where actors would wear masks to portray their characters. When they were off-stage they would switch masks and become another character. To accept this, one would have to omit “the Word was with God”(13) in John 1:2, that God was in all three modes at once during the baptism of Jesus (21), and that Jesus was asking Himself to let the cup of His wrath pass from Him in the Garden of Gethsemane (22).

Arianism, taught by a popular preacher named Arius, is the belief that Jesus Christ was the first created being. This belief was so widespread by many layfolk and emperors alike that it caused the first major church-wide council to be formed at Nicaea. The church fathers at the Council of Nicea created the Nicene Creed (later expanded as the Nicene-Constanipolitan Creed) to combat the Arian Heresy and to defend that Jesus Christ is truly God, that He was “in the beginning with God.” (14)

Tritheism is the idea that there are three [tri] gods [theos.] Each person of the Trinity is believed to have a separate essence and will. To affirm tritheism is to corrupt the Shema to read, “the Lord[s] our God[s], the Lord[s] [are not] one.

A more modern controversy, termed Eternal Functional Subordination or Eternal Subordination of the Son, seeks to redefine the Trinity as a society where the Son is, from all eternity, submitting to the will of the Father. The issue with Eternal Functional Subordination is that it denies Inseparable Operations. This says that there is only one will of God, and instead asserts that the Father, the Son, and the Spirit all have separate wills and that the Son, along with the Spirit submits His will to the Father’s will. This idea drifts dangerously towards Tritheism as it gives God a multitude of wills, and perhaps a multitude of separate centers of consciousness.

Conclusion

The doctrine of the Trinity defines who God is. If we reject it, we do not serve the God of Abraham, of Isaac, of Jacob and of Moses. The primary issue of studying and understanding the Trinity, as far as it has been revealed to us, is a problem of vocabulary. By not studying the trinity, we do not know how to talk about who God is. Jehovah’s Witnesses, Mormons, and Unitarians embrace the same errors that Arians, Tritheists, and Sabellians put forward millenia ago. “For a great many ideas about God which are trotted out as novelties today are simply the ones which real Theologians tried centuries ago and rejected.”(23) To seek after God, we must follow Him as He has revealed Himself in the Bible and as He has revealed Himself in Trinity.