Here are what a few long-time professional theologians say about it. They will keep your thoughts in order—or show you how much a mystery the Trinity is!
Don’t feel frustrated if you have to read this post several times. Tough ideas are difficult in the first, second or third rounds of study—or more rounds! But gradually you will get it.
These are some of the theologians.
Let’s start with the simplest excerpt:
Elmer L. Towns:
Christians believe in one God in three persons: Father, Son, and Holy Spirit. Each member of this Trinity is God and works in our lives as Christians. As God, each is worthy of our worship and deserving of our obedience. They have revealed themselves and what they expect of us in the Bible. The desire of every Christian ought to be to love, worship, and obey the Triune God (p. 99)
Translation: God is one in essence (monotheism) and reveals himself in Scripture in three persons (trinitarian monotheism). Our response to the Father, Son, and Holy Spirit living, acting and moving in us as one God is to love, worship, and obey him.
I hope people memorize Town’s short paragraph, especially the first sentence.
Pentecostal theologian French Arrington:
God is a unified being. There is not just one but three persons in the Godhead. There is the Father who is the Creator and source of all things. There is the Son who redeems us. There is the Holy Spirit who regenerates, sanctifies, and fills us with His power. Each has his own identity. The distinct identity of each was evident at the baptism of Jesus. The Son of God was standing in the Joran [River]. He was anointed by the Holy Spirit, who came upon Him in the form of a dove, and the Father spoke from heaven (Luke 3:21, 22). (vol. 1, p. 137)
Translation: One God in three persons—Father-, Son, and Holy Spirit—who share the same essence but have different roles in relating to their creation.
Reformed theologian Louis Berkhof:
It is generally admitted that the word “persons” is but an imperfect expression of the idea [of the Trinity existing as the Father, Son, and Holy Spirit]. In common parlance it [“person”] denotes a separate rational and moral individual, possessed of self-consciousness, and conscious of his identity amid changes. Experience teaches that where you have a person, you also have a distinct individual essence. Every person is a distinct and separate individual, in whom human nature is individualized. But in God there are three individuals alongside of, and separate from, one another, but only personal self-distinctions within the Divine essence … which is one. (p. 87)
Translation: If you stand Abraham, Isaac and Jacob next to each other, they are separate persons and do not have a united, single essence. The trinitarian God does manifest or reveal himself in three persons, Father, Son, and Holy Spirit, but they have the identical essence (one God), which three humans persons cannot have. So the term person is inadequate, but it will have to do.
Presbyterian-Charismatic Renewal theologian J. Rodman Williams in outline:
God is one … in three persons … Father, Son, Holy Spirit … each person is God … One God in three persons … The persons of the Godhead are distinct,
Then he writes fully:
The Father is God, the Son is God, and the Holy Spirit is God. There are not three Gods, but only one. Christian faith is not tri-theistic. The Father is the one and only God, so likewise are the Son and Holy Spirit. Thus the Father is totally God, the Son is totally God, and the Holy Spirit is totally God: there is no depth, width, or breadth of the divine reality that is not fully Father, Son, and Holy Spirit. … Hence, Father, Son and Holy Spirit are the same essence. … Thus Father, Son, and Holy Spirit, while differing personally, do not differ essentially. The whole undivided essence belongs to each of the three persons. (vol. 1, pp. 83-90)
Translation: One God in three persons—Father, Son, and Holy Spirit—who share the same essence or nature in totally, yet the three persons are distinct in their roles and relationships.
Reformed Renewal theologian Wayne Grudem:
1.. God is three persons
2.. Each person is fully God
3.. There is one God.
The fact that God is three persons means that the Father is not the Son; they are distinct persons. It also means that the Father is not the Holy Spirit, but that they are distinct persons. And it means that the Son is not the Holy Spirit. (p. 231)
Translation: The three premises are clearly taught in Scripture, and Prof. Grudem goes on to distinguish the three persons, so we don’t merge or “con-fuse” (flow together) them beyond distinction. But each person is contained within God.
Certainly we can understand and know that God is three persons and that each person is fully God, and there is one God. We can know these things because the Bible teaches them … But what we cannot understand fully is how to fit together those distinct biblical teachings … In fact, it is spiritually healthy for us to acknowledge openly that God’s very being is far greater than we can ever comprehend. This humbles us before God and draws us to worship him without reservation. (p. 256)
Translation: We can read the Bible and see the Father, Son, and Holy Spirit working there, but his essence is hard for us to comprehend. So let’s approach God with humility and wonder and worship.
Reformed theologian James I. Packer:
The historic formulation of the Trinity (derived from the Latin word trinitas, meaning “threeness”) seeks to circumscribe and safeguard the mystery (not explain it; that is above us) and it confronts us with perhaps the most difficult thought that the human mind has ever been asked to handle. It is not easy, but it is true (p. 40)
Translation: Defining the threeness of God seeks to protect it from bad teaching, not explain it fully. Explaining it completely is beyond us, but the doctrine is true.
Evangelical Dictionary of Theology:
This doctrine is above reason but not contrary to reason, though there have always been Christians who enjoyed stating it as a stark paradox (“God is three yet somehow one,” omitting the clarifying nouns). They mystery of the doctrine of the Trinity lies in the difficulty of conveying how a single being can be three persons, because we have no available examples of such a thing, and any such examples would not be God anyway.
Translation: Some Christians seem to delight in being simplistic about it and leave out certain nouns. It is correct to say, “God is three persons, yet somehow one being.” Different terms in italics. We are bereft of examples of how that can happen, so the Trinity appears to be a mystery to us.
So how does knowing about the Trinity help me know God better?
There is an entire ten-point post that answers that question, here:
Written by James Malcolm
ARTICLES IN THE TRIUNITY SERIES
The Trinity: What Do Theologians Say?