The Eastern and Western churches have understood the Trinity in rather different ways, each with distinct problems. For the East, the person of the Father is the center of divine unity. The potential danger is a subordinationist tendency, with the Son and the Holy Spirit having a derivative status. On the other hand, the West, since Augustine, has focused on the one divine essence (being), only with difficulty accounting for the real eternal distinctions between the persons. A less-than fully personal view of God has resulted. Its bias is in a modalist direction, wherein the distinct persons are blurred. Unfortunately, the Trinity is not a vital part of worship; for Western Christians, it is a mathematical conundrum, a matter for advanced philosophers, not ordinary believers. Conversely, the Eastern church, while maintaining the Trinity at the heart of worship, has taught that the divine essence is unknowable, placing a question mark over the reality of our knowledge of God. Some recent Western theologians, such as Jürgen Moltmann, argue that the Trinity is a community of three equal persons. However, by correlating the Trinity with human history and experience, their conclusions veer towards panentheism, in which God and the world are co-dependent.
By observing each of the following crucial factors, we can avoid many dangers.
God is one being — three persons. He is three persons — one being.
God is a union of three persons and therefore is fully personal; indeed, He created human persons. The three persons and the one being of God are equally ultimate. God is three, irreducibly distinct persons in indivisible union, one God in three inexpressibly different ways. That God is one being (essence, from esse, to be) is axiomatic. That the one eternal being of God is three distinct persons is essential to salvation, for otherwise the truth of God’s revelation would be destroyed. The Bible presents creation and salvation as works of God. Since the Son and the Holy Spirit are, with the Father, direct and distinct personal actors in both realms, all three are God.
Both sides of this statement are equally ultimate. Here Gregory Nazianzen (330–91) is brilliantly helpful, in a passage that Calvin found a vast delight: “No sooner do I conceive of the one than I am illumined by the splendour of the three; no sooner do I distinguish them than I am carried back to the one. When I think of any one of the three I think of him as the whole, and my eyes are filled, and the greater part of what I am thinking escapes me. I cannot grasp the greatness of that one so as to attribute a greater greatness to the rest. When I contemplate the three together, I see but one torch, and cannot divide or measure out the undivided light” (Oration on Holy Baptism).
The three persons are of the same identical being (homoousios).
It follows that the one, identical divine being is possessed by the Father, the Son, and the Holy Spirit. All three persons are of one substance (consubstantial) or, better, of the identical being (homoousios). Furthermore, each person is God-in-Himself. Neither the Son nor the Holy Spirit derive their deity from the Father. The begetting of the Son and the procession of the Spirit refer to the relations between the persons, not to the essence or being of God as such. The credal statements (“light of light,” “true God of true God”) were understood by the tradition to refer to this identity of being.
Each Trinitarian person is one hundred percent God, and one hundred percent of God is in that person; the whole God is in each person, and each person is the whole God. At the same time, the being of God is not divisible, but simple. It is impossible to cut off and detach part of God, leaving the rest behind. It is possible to remove a human kidney from its owner and transplant it into another person, but God cannot be divided. That is why the three persons comprise all of God both severally and together. God cannot be apportioned to the several persons in amounts less than the whole of who He is. Consequently, the whole of God is in each person and each person is the whole God. It follows that there is no more of God in all three persons together than there is in any one of them.
Since all three are one identical being, no one person is of higher or lesser status than the other. There are no gradations of deity. Since the three are one identical being, they are equal in power and glory, working together inseparably in all God’s works of creation, providence, and grace. All three together are worshiped.
The three persons mutually indwell one another in a dynamic union.
Since all three persons are fully God, and the whole God is in each of the three, the three mutually contain one another. As Gerald Bray writes, all three occupy the same divine space. Their union is unbreakable and the three are inseparable. Here divine and human persons differ. Human persons do not exist in one another as the divine persons do. We are not only distinct but apart. We act differently, we go our separate ways, some are healthy and live long while others die young. Moreover, there are a huge number of human beings, the total increasing or diminishing as time goes by. But the divine persons are three — no more, no less — and are so eternally without change. This is not an indwelling that submerges the particularities of any of the three. These are dynamic, living relations. This is important now that Islam has reappeared on the radar, with its stress on unity-without-diversity.
The three persons are irreducibly different.
This is evident in the incarnation, in which the Son took into everlasting personal union a human nature. This the Father and the Holy Spirit did not do. So too the Holy Spirit — not the Father or the Son — was sent at Pentecost. The three are irreducibly different from each other in ways we cannot understand. This is not to the detriment of the indivisible action of the three, for they work together as one. Modalism confuses or eclipses the personal distinctions, whereas our salvation depends on them, or God’s self-revelation in history would not be true to who He is eternally.
There is an order between the persons.
This order is: from the Father through the Son by the Holy Spirit. These relations cannot be reversed — the Son does not beget the Father, nor does the Father proceed from the Holy Spirit. In this sense, the Father is the first, the Son the second, and the Holy Spirit the third. These particular relations the three persons sustain to each other are inseparable from who they are and so are eternal and unchangeable.
Thus, the Father is the Father of the Son, and the Son is the Son of the Father. The Father begets the Son, the Son is begotten by the Father. This relation is neither interchangeable nor reversible. So also the Holy Spirit proceeds from the Father and the Son, while the Father and the Son spirate the Spirit. This is never reversed. The Father is neither begotten nor proceeds, the Son does not beget nor does He proceed, the Spirit neither begets nor spirates. These relations exist in the context of the mutual indwelling of the three. Indeed, the Spirit is the Spirit of the Son, entailing the Father as the Father of the Son. There is a distinction (not a division) between the three as they distinctly and together constitute the one undivided being of God, and the three in their distinct personal relations. John Calvin sums this up in saying that the Son is God of Himself, whereas in terms of relations He is from the Father (Institutes of the Christian Religion 1.13.25). This order is not a rank or hierarchy but an appropriate disposition.
A doctrine of the Trinity faithful to the Bible must give equivalent expression to each of these parameters. These parameters are mutually defining. The three persons are irreducibly different and are one identical being. There is an order between them and they mutually indwell each other, are equal in status, one in being. They mutually indwell one another and are irreducibly different.
This will enhance our worship and worldview.
Our worship and prayer is Trinitarian (Eph. 2:18), while the unity-in-diversity of the world directs us to the Holy Trinity; widespread appropriation of Trinitarian doctrine will secure a foundation for healthy, human relationships — personal, ecclesiastical, social, and political.