The doctrine of the Trinity is foundational to the faith and worship of the Church. There is one God who eternally subsists as three persons, Father, Son, and Holy Spirit. Each person is unique and distinct within the godhead and at the same time fully God. The trinity of persons is not to be understood as differing modes of being. The Son is fully God at the same points in and before time as the Father and Spirit. In upholding plurality we must not abandon essential unity. Within Orthodox developments, this has been the ecumenical consensus with differing emphasis in formulation. Over time the church has continued to develop the distinctions that it uses when discussing this doctrine. These distinctions are economic, ontological, and social reflections on the Trinity. The economic Trinity is the revealed activity of God in Scripture. In creation and redemption we see God revealed as he is for us. We do not know God apart from the economic revelation of himself to humanity. The ontological Trinity is the revelation of God as he is in himself. This is the hiddenness of God. The economic revelation of God limits our understanding of God as he is in himself. There is more to say about God, but we do not know what that is apart from God’s revelation of himself in relation to humanity. The social Trinity is the revelation of the communion of God. The ontological and social Trinity are hinted at in God’s activity and self-revelation in Scripture. These categories helpfully promote further reflection on the historic consensus. Now as always, the Church must guard the historic understanding of this doctrine from innovation as it continues to confess that God is one in essence and three in persons.
God is one, and he alone is to be worshipped. Monotheism and the worship of that one God alone are affirmed in both the Old and New Testaments. This was Israel’s creed and Jesus’ response to Satan in his wilderness temptation (Mt. 4:10). The unity of God in the New Testament is undisputed. It is the plurality of the one God that has sparked controversy. Once you see Jesus as the center of the Old Testament text (Lk. 24) you also see that the Old Testament possesses hints of plurality (i.e., the Angel of the Lord in Genesis 18, 22, 32 and Exodus 3, and the Angel of God’s Presence in Isa 63). Despite Israel’s strict monotheism, the personal name of God, YHWH, is identified with the Angel of the Lord (Zechariah 3:1-4). A similar move occurs in Rev. 1:8 where Jesus is referred to in language reminiscent of Isa. 44:6. The LORD of hosts is the first and the last, and besides him there is no God. There is one God, the Father and Creator, and one Lord Jesus Christ through whom we exist (1Co 8:6). In the Jewish context, Jesus’ divinity is strongly asserted in that there is no other name in heaven or on earth by which men may be saved. The Father and the Son receive the same titles and worship. Jesus is the only Son from the Father (John 1:14), he was with the Father from the beginning and is identified with the same being as the Father (John 1:1-3); Jesus is viewed as pre-existent, identical to God, and distinct from the Father. This divine status also extends to the Holy Spirit (Acts 5:4). The Spirit is involved in Creation (Gen. 1:2; Job 26:13; 33:4), providence (Ps 104:30), regeneration (Jn 3:5-6; Tit. 3:5) and the resurrection of the dead (Ro 8:11). The Spirit is spoken of as sent by the Father and the Son, just as the Son is also sent by the Father. This participation in the economy of salvation is a participation of all the persons of the Trinity in all aspects of the planned work of the Father. While the Old Testament contains hints of plurality, the New Testament is explicit in its numerous triadic expressions. The triadic formulas are present in baptism, and the liturgical blessings and benedictions. Surprisingly, the early Jewish believers worshipped each person equally as God. It is significant that before the historic definition of the Trinity these triadic expressions pervaded the Church’s faith, worship, sacraments, and prayer.
The triadic nature of the economic Trinity attained an early consensus in the Church. Early controversy centered on the philosophical meaning of the terms employed and on how the economic distinctions relate to the eternal reality of God-in-himself. One popular solution argued that God is one person (i.e., the Father), and that the one God manifested himself at different times as the Son and the Spirit. This position is known as modalism and was founded by Sabellius, a third century Roman presbyter. Modalism maintained the unity of God at the expense of the plurality. This position was ruled out according to the biblical understanding outlined above. Furthermore, modalism created an ethical dilemma for the Church. A similar error that gained popularity in the early Church argued for the unity of God (i.e., the Father) and the ontological subordination of the Son and the Spirit to the one God (i.e., lesser gods). This position was held by Origen, Eusebius, and the Arians. Their objection to the orthodox position came from an Aristotelian understanding of essence (ousia). For Aristotle, essence refers to both the individual who bears the essence, as well as the essence itself. Simply put, essence referred to both the nature and the person. This understanding contributed to confusion in early discussions. According to this definition of essence, if God is one essence, then he cannot be three. God cannot be three in the same way that he is one. This confusion was unfortunate, because no one actually affirmed “one in essence, three in essence.” In light of our previous discussion, ontological subordination is ruled out as an option because of the titles and worship given to the Son, as well as the identification of the Word with God. It is not that the Father and the Son have a similar divine essence (i.e., the position of the semi-Arians); Scripture demands that the persons of the Trinity be understood as the same in essence, and equal in power and glory.
It was not until the fourth century that the Church possessed the categories to make the necessary distinction between essence and person (hypostasis) in a manner that did not contribute to misunderstanding. Tertullian had already coined the formula “one in essence and three in persons” by the second century, but it was not until the contribution of the Cappadocians that the formula was advanced in a manner that the East and West could agree on. This new language rescued the “person” distinction from being a subcategory of essence and allowed for further ontological distinction in the debate. The Father has a unique personhood from the Son and the Spirit, and he shares in the common essence and attributes. This is in contradistinction to the idea that the Father is a persona that the one God acts out on the stage of history. It is also not enough to say that there is fatherhood, sonship, and love within the one God. The “person” distinction is an ontological distinction and not a relational distinction only. Nevertheless, this relational understanding is important because it emphasizes that the Father is not the Father apart from the Son and that the Father, Son, and Spirit must necessarily have existed in perfect relational community in eternity. This is another way of saying that there never was a time when the Son did not exist. When we consider the one essence apart from the three persons we inadvertently fall into Arianism, and when we meditate on the three persons apart from the one essence we fall into polytheism. This revolutionary distinction in the debate eventually led to the Church reaching an ecumenical consensus. The retrieval of this controversy is essential to Trinitarian reflection, as well as the defense of the Orthodox position against those sects that hold similar positions to the ones outlined above.
With differing emphases, the East and West rejected Tritheism, Subordinationism, and modalism. God’s essence is undivided and that undivided essence is shared in common with three persons. The Trinitarian sharing of essence is not in parts, but in the whole. Whatever attribute applies to God, applies to the Father, Son, and Spirit equally. If this was all that was said, then there would be a hint of modalism in our statement. We must also state that the Son is begotten, and not the Father or the Spirit; that the Father is father, and not the Son or the Spirit; and that the Son and the Spirit are sent, and that the Father is the one who sends. The three persons are each God in themselves (autotheos), while the three eternal hypostasis have their origin from the Father; only the Father is unbegotten, only the Son is eternally begotten, and only the Spirit is eternally sent. The distinction of undivided essence and eternally originated personhood safeguards from both the ontological subordination of Origen and the modalism of Sabellius. The examples of differentiation in the persons multiply if we further consider the history of redemption in light of the relationship between the economic and ontological Trinity (i.e., the Father could not become incarnate, the Spirit is not the head of the body, etc). This is why it must be stated that the repetition of the one essence in the persons does not obscure the uniqueness of the persons. The persons are more than repetitions of the same essence. God is personal and not a person. To conceive of God as a person, and triunity as an attribute of that one person, is to slip into a deceptive version of modalism. The Subordinationist objection to plurality in the divine essence falls flat precisely because plurality refers to persons and not essence. If we understand tri-unity as an attribute of God, then we bring plurality back into essence. This subtle modalistic error weakens the orthodox defense against modern expressions of Subordinationism. With the East, we must continue to affirm that plurality belongs to the hypostasis and not the ousia.
The Cappadocian achievement had further ramifications on the Trinitarian spirituality and worship of the Church. When we encounter the Son through the Spirit we encounter a person of the Trinity and not the divine essence. The Trinitarian community that the believer participates in is a social and mysterious participation among persons, and not ascension up the ladder of being and into the divine essence. There is no essence hiding above the hypostasis; the entirety of the essence is found in the unique and distinct persons. There is no communion with God apart from the three-in-one. This makes spirituality possible. It is in union with the Incarnate Son that humanity may participate in the fellowship of Father, Son, and Holy Spirit. Only in the God-man may man fellowship with God. The eternal, intra-Trinitarian relation of persons may be seen in how the persons of the ontological Trinity relate in their economic mission. The Son is uniquely the son of the Father in his redemptive mission (John 4:34). The Father, Son, and Spirit share a mission in common, but they all participate in that mission in a manner distinct to their persons. This upholds the distinction between essential attributes and personal attributes outlined above. The social unity of the persons is found in their mutual indwelling. There is both an essential unity and a unity of the community of persons (John 17:21). If you look for the unity of God in mutual indwelling only, then you advocate the worship of three gods and compromise the true oneness of that holy family. Similarly, when man participates in this Trinitarian fellowship, he participates personally and not essentially. It is to the person of the Incarnate Son that the Spirit unites believers and not to the one essence.
The Trinity is more than a doctrine and is the whole of the Christian faith. Worship of the Trinity is the end of all theological reflection. The understanding of the Trinity that this essay has sought to outline has attempted to listen to both the eastern and western Trinitarian formulations and debates, alongside Scripture as the norming norm. This reflection has resulted in an understanding of the social Trinity distinct from the trinitarian panentheism (i.e., unity in relations through mutual indwelling only) that is growing in popularity. Any error here will have devastating consequences throughout the entire range of systematic theology. In the end, though, all reflections are analogical and directed toward the Economic Trinity. Apart from God’s revelation of himself there is no knowledge of God’s intra-Trinitarian relations. Furthermore, the economic Trinity cannot say all that is to be said about the ontological Trinity. The Trinity is an incomprehensible mystery revealed in Scripture and must be approached with reverence and awe; the result of this study must be the renewal of biblical faith, worship, and practice.