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TRINITY . Trinitarian doctrine touches on virtually every aspect of Christian faith, theology, and piety, including Christology and pneumatology, theological epistemology (faith, revelation, theological methodology), spirituality and mystical theology, and ecclesial life (sacraments, community, ethics). This article summarizes the main lines of trinitarian doctrine without presenting detailed explanations of important ideas, persons, or terms.

The doctrine of the Trinity is the summary of Christian faith in God, who out of love creates humanity for union with God, who through Jesus Christ redeems the world, and in the power of the Holy Spirit transforms and divinizes (2 Cor. 3:18). The heart of trinitarian theology is the conviction that the God revealed in Jesus Christ is involved faithfully and unalterably in covenanted relationship with the world. Christianity is not unique in believing God is "someone" rather than "something," but it is unique in its belief that Christ is the personal Word of God, and that through Christ's death and resurrection into new life, "God was in Christ reconciling all things to God" (2 Cor. 5:19). Christ is not looked upon as an intermediary between God and world but as an essential agent of salvation. The Spirit poured out at Pentecost, by whom we live in Christ and are returned to God (Father), is also not a "lesser God" but one and the same God who creates and redeems us. The doctrine of the Trinity is the product of reflection on the events of redemptive history, especially the Incarnation and the sending of the Spirit.

Development of Trinitarian Doctrine

Exegetes and theologians today are in agreement that the Hebrew Bible does not contain a doctrine of the Trinity, even though it was customary in past dogmatic tracts on the Trinity to cite texts like Genesis 1:26, "Let us make humanity in our image, after our likeness" (see also Gn. 3:22, 11:7; Is. 6:23) as proof of plurality in God. Although the Hebrew Bible depicts God as the father of Israel and employs personifications of God such as Word (davar), Spirit (rua), Wisdom (okhmah), and Presence (shekhinah), it would go beyond the intention and spirit of the Old Testament to correlate these notions with later trinitarian doctrine.

Further, exegetes and theologians agree that the New Testament also does not contain an explicit doctrine of the Trinity. God the Father is source of all that is (Pantokrator) and also the father of Jesus Christ; "Father" is not a title for the first person of the Trinity but a synonym for God. Early liturgical and creedal formulas speak of God as "Father of our Lord Jesus Christ"; praise is to be rendered to God through Christ (see opening greetings in Paul and deutero-Paul). There are other binitarian texts (e.g., Rom. 4:24, 8:11; 2 Cor. 4:14; Col. 2:12; 1 Tm. 2:56, 6:13; 2 Tm. 4:1), and a few triadic texts (the strongest are 2 Cor. 13:14 and Mt. 28:19; others are 1 Cor. 6:11, 12:46; 2 Cor. 1:2122; 1 Thes. 5:1819; Gal. 3:1114). Christ is sent by God and the Spirit is sent by Christ so that all may be returned to God.

The language of the Bible, of early Christian creeds, and of Greek and Latin theology prior to the fourth century is "economic" (oikonomia, divine management of earthly affairs). It is oriented to the concrete history of creation and redemption: God initiates a covenant with Israel, God speaks through the prophets, God takes on flesh in Christ, God dwells within as Spirit. In the New Testament there is no reflective consciousness of the metaphysical nature of God ("immanent trinity"), nor does the New Testament contain the technical language of later doctrine (hupostasis, ousia, substantia, subsistentia, prosōpon, persona). Some theologians have concluded that all postbiblical trinitarian doctrine is therefore arbitrary. While it is incontestable that the doctrine cannot be established on scriptural evidence alone, its origins may legitimately be sought in the Bible, not in the sense of "proof-texting" or of finding metaphysical principles, but because the Bible is the authoritative record of God's redemptive relationship with humanity. What the scriptures narrate as the activity of God among us, which is confessed in creeds and celebrated in liturgy, is the wellspring of later trinitarian doctrine.

Dogmatic development took place gradually, against the background of the emanationist philosophy of Stoicism and Neoplatonism (including the mystical theology of the latter), and within the context of strict Jewish monotheism. In the immediate postNew Testament period of the Apostolic Fathers no attempt was made to work out the God-Christ (Father-Son) relationship in ontological terms. By the end of the fourth century, and owing mainly to the challenge posed by various heresies, theologians went beyond the immediate testimony of the Bible and also beyond liturgical and creedal expressions of trinitarian faith to the ontological trinity of coequal persons "within" God. The shift is from function to ontology, from the "economic trinity" (Father, Son, and Spirit in relation to us) to the "immanent" or "essential Trinity" (Father, Son, and Spirit in relation to each other). It was prompted chiefly by belief in the divinity of Christ and later in the divinity of the Holy Spirit, but even earlier by the consistent worship of God in a trinitarian pattern and the practice of baptism into the threefold name of God. By the close of the fourth century the orthodox teaching was in place: God is one nature, three persons (mia ousia, treis hupostaseis).

Questions of Christology and soteriology (salvation) occupied theologians of the early patristic period. What was Christ's relationship to God? What is Christ's role in our salvation? The Logos Christology of the apologists identified the preexistent Christ of Johannine and Pauline theology with the Logos ("word") of Greek philosophy. The Stoic distinction between the immanent word (logos endiathetos) and the expressed word (logos prophorikos) provided a way for Justin Martyr (d. 163/165) and others to explain how Christ had preexisted as the immanent word in the Father's mind and then became incarnate in time. Third-century monarchianism arose as a backlash against Logos theology, which was feared to jeopardize the unity of God; the modalism of Sabellius admitted the distinctions in history but denied their reality in God's being. Origen (died c. 254) contributed the idea of the eternal generation of the Son within the being of God; although other aspects of Origen's theology later were judged to be subordinationist, his teaching that the Son is a distinct hypostasis brought about subtle changes in conceptions of divine paternity and trinity. In the West, Tertullian (d. 225?) formulated an economic trinitarian theology that presents the three persons as a plurality in God. Largely because of the theology of Arius, who about 320 denied that Christ was fully divine, the Council of Nicaea (325) taught that Christ is homoousios (of the same substance) with God. The primary concern of Athanasius (d. 373), the great defender of Nicene orthodoxy, was salvation through Christ; if Christ is not divine, he cannot save. Like the bishops at Nicaea, Athanasius had a limited trinitarian vocabulary; hupostasis (person) and ousia (substance) could still be used interchangeably.

The fourth-century Cappadocian theologians (Basil of Caesarea, Gregory of Nyssa, and Gregory of Nazianzus) formulated orthodox trinitarian doctrine and made it possible for the Council of Constantinople (381) to affirm the divinity of the Holy Spirit. The speculatively gifted Cappadocians made a clear distinction between hupostasis and ousia (roughly equivalent to particular and universal), thereby establishing orthodox trinitarian vocabulary. At the close of the patristic period John of Damascus (d. 749) summarized Greek trinitarian doctrine with the doctrine of perichōresis (Lat., circumincessio), or the mutual indwelling of the divine persons.

Western trinitarian theology took a different course because of Augustine (d. 430). Instead of regarding the Father as source of divinity, Augustine's starting point was the one divine substance, which the three persons share. He sought the image of the Trinity within the rational soul and formulated psychological analogies (memory, intellect, will; lover, beloved, love) that conveyed unity more than plurality. The Augustinian approach served to effectively refute Arianism, but it also moved the doctrine of the Trinity to a transcendent realm, away from salvation history, from other areas of theology, and from liturgy. In the Latin West Boethius (died c. 525) formulated the classic definition of person, namely, "individual substance of a rational nature." Augustinian theology was given further elaboration in medieval theology, especially by Anselm (d. 1109) and in the Scholastic synthesis of Thomas Aquinas (d. 1274). Still Augustinian but focusing on person rather than nature, Richard of Saint-Victor (d. 1173) and Bonaventure (d. 1274) developed a psychology of love; charity is the essence of Trinity.

Although there are important exceptions to any typology, in general, Greek theology emphasizes the hypostases, the "trinity in unity," whereas Latin theology emphasizes the divine nature, or "unity in trinity." The Greek approach can be represented by a line: Godhood originates with the Father, emanates toward the Son, and passes into the Holy Spirit who is the bridge to the world. Greek theology (following the New Testament and early Christian creeds) retains the "monarchy" of the Father who as sole principle of divinity imparts Godhood to Son and Spirit. The Greek approach tends toward subordinationism (though hardly of an ontological kind) or, in some versions, to tritheism since in Greek theology each divine person fully possesses the divine substance. The Latin approach can be represented by a circle or triangle. Because the emphasis is placed on what the divine persons share, Latin theology tends toward modalism (which obscures the distinctiveness of each person). Also the Trinity is presented as self-enclosed and not intrinsically open to the world.

Principles of Trinitarian Doctrine

Trinitarian theology is par excellence the theology of relationship. Its fundamental principle is that God, who is self-communicating and self-giving love for us, is from all eternity love perfectly given and received. The traditional formula "God is three persons in one nature" compactly expresses that there are permanent features of God's eternal being (the three persons) that are the ontological precondition for the three distinct manners of God's tripersonal activity in the world (as Father, Son, Spirit).

Technical terms, theological theories, and official (conciliar) statements function together as a "set of controls" over the correct way to conceive both of God's self-relatedness as Father, Son, and Spirit, and God's relatedness to creation as Father, Son, and Spirit. Although one must guard against reducing the mystery of God to a set of formal statements, precise distinctions are useful insofar as they refine theological vocabulary or protect against distortions ("heresy"). Still, doctrinal statements are inherently limited; they address specific points of controversy, leaving other questions unsettled and sometimes creating new problems. Conciliar statements and theological principles guard against egregious errors (for example, "the Holy Spirit is a creature") and serve as boundaries within which trinitarian discourse may take place.

First, God is ineffable and Absolute Mystery, whose reality cannot adequately be comprehended or expressed by means of human concepts. Trinitarian doctrine necessarily falls short of expressing the full "breadth and length and height and depth" of God's glory and wisdom and love. Even though God who "dwells in light inaccessible" is impenetrable mystery, the doctrine of the Trinity is not itself a mystery, nor is the doctrine revealed by God, nor is the doctrine a substitute for the knowledge of God gained in the union of love that surpasses all concepts (see Eph. 3:1819). Trinitarian doctrine is a partial and fragmentary exegesis of what has been revealed, namely, that God is self-communicating love. Further, because God is a partner in love and not an object to be scrutinized or controlled by the intellect, speculative theology must be firmly rooted in spirituality, doxology, and a concrete community of faith so that trinitarian doctrine does not become "heavenly metaphysics" unrelated to the practice of faith.

Second, the revelation and self-communication of the incomprehensible God, attested in the concrete images and symbols of the Bible and celebrated in Christian liturgy, is the proper starting point of trinitarian theology. Theological thinking proceeds from "God with us" ("economic" Trinity) to the nature of God ("immanent" Trinity). The starting point "within" God led to an overly abstract doctrine in the West and to a virtual divorce of the "immanent" Trinity from the Trinity of history and experience. Friedrich Schleiermacher (d. 1834) reacted against the cleavage between "God" and "God for us" by relegating the idea of the essential Trinity to an appendix to his summary of Christian theology. Karl Rahner's (d. 1984) widely accepted axiom is pertinent: "the 'economic' Trinity is the 'immanent' Trinity and vice versa." God is who God reveals God to be. Concepts that describe the ontological intrarelatedness of God must be drawn from and are subject to control by the "facts" of redemptive history.

Third, because the three persons together and inseparably (though without mingling or confusion) bring about salvation and deification, and because the one God is worshiped as Father, Son, and Spirit, no divine person is inferior to any other person. Although undivided, God exists as the pure relationality of love given and received. The decree of the Council of Florence (1442) that "everything in God is one except where there is opposition of relation" was regarded as a final answer to tritheism (belief in three gods), Arian subordinationism (ontological hierarchy of persons), Sabellian modalism (no real distinctions "in" God), and Macedonianism (denial of the divinity of the Holy Spirit).

There are two divine processions: begetting and spiration ("breathing"). Each divine person exists by relation to the other two persons (Gr., "relation of origin"; Lat., "relation of oppositon"), and each fully possesses the divine substance. In Greek theology the three hypostases have the distinguishing characteristics (sg., idiotes ) of "being unbegotten" (agennēsia), "being begotten" (gennēsia), and "proceeding" (ekporeusis). The Father is the fountainhead of Godhood (fons divinitatis), who imparts divinity to Son and Spirit. According to Latin theology there are four relations (begetting, being begotten, spirating, being spirated) but only three "subsistent" relations: paternity, filiation, spiration. Latin theology (following Augustine) understands divine unity to reside in the divine nature that is held in common by Father, Son, and Spirit; Greek theology (following the Cappadocians) understands the unity to reside in the "perichoretic" relatedness of the three persons.

A corollary of the inseparability of the three coequal divine persons is the axiom that "all works of the triune God ad extra are indivisibly one" ("opera trinitatis ad extra indivisa sunt"). According to Latin theology it is the three-personed substance of God that acts in history; according to Greek theology every action of God toward creation originates with the Father, passes through the Son, and is perfected in the Spirit (Gregory of Nyssa). In any case, the axiom must not be understood to obscure what is distinctive to each divine person.

Fourth, a false distinction must not be set up between what God is and what God does, between essence and existence, between unity and threefoldness, between nature and person (relation). There are no "accidents" in God; the statement of the Fourth Lateran Council (1215) that each divine person is the divine substance countered the claim of some theologians (Joachim of Fiore) that God is a quaternity (three persons + essence = four persons).

Fifth, since the nature of God is to love, and love naturally seeks an object, it might appear that God "needs" the world as a partner in love. This would make the world coeternal with God. Many Scholastic theologians speculated on this question. Thomas Aquinas admitted that while he saw no philosophical reason to deny the eternity of the world, the testimony of the Book of Genesis and his Christian faith constrained him to do so. In 1329 Meister Eckhart was condemned for asserting the eternity of the world. With respect to trinitarian theology, even though Rahner's axiom (see above) suggests that God's relations to us, including creation, are constitutive of God and vice versa, theologians traditionally speak of a perfect and reciprocal exchange of love "within" God, that is, among Father, Son, and Spirit independent of their relationship to creation, in order to preserve the absolute character of God's freedom.

Current Directions and Remaining Problems

After centuries of disinterest in trinitarian doctrine in the West, the riches of this vast tradition are once again being explored. Three basic directions may be observed. First, some theologians have revised analogies of the "immanent" Trinity according to contemporary philosophy (for example, process metaphysics), linguistics, or interpersonal psychology. While this approach overcomes some of the aporia of classical expositions, it perpetuates the metaphysical starting point "within" God apart from salvation history. A second approach focuses on soteriology and Christology and is circumspect about the "immanent" Trinity, though without denying that historical distinctions are grounded ontologically in God. A third approach uses trinitarian symbolism to describe God's deeds in redemptive history but resists positing real distinctions in God. Despite basic differences in method, these three approaches all move in a more personalist (relational) direction and, in the case of the latter two, a more "economic" direction.

Theologians who specialize in trinitarian doctrine suggest that several areas warrant further attention. First, most trinitarian doctrine is so abstract it is difficult to see its connection with praxis. The "summary of Christian faith" and the living out of that faith should be brought to bear more directly on each other. Creeds, doxologies, and liturgy are important loci of the trinitarian faith recapitulated in trinitarian doctrine.

Second, unlike the "mystical theology" of the Orthodox tradition, theology in the West has been separated from spirituality since the thirteenth century. Reintegrating theology and spirituality would help to overcome the rationalist tendencies of Western theology, to provide the field of spirituality with theological foundation, and also to strengthen the weakest component of Western theology, namely, pneumatology.

Third, the filioque ("and from the Son") clause, inserted into the Western creed in the sixth century but denounced by the Orthodox church, remains a serious obstacle to reunion between East and West. Theologians should work assiduously for ecumenical agreement.

Fourth, to speak of God as "three persons" always has been problematic and remains the same today. In the modern framework "person" means "individual center of consciousness." To avoid the tritheistic implications of positing three "persons" in God, the relational, or "toward-the-other" character of "person" should be reemphasized.

Fifth, the exclusively masculine imagery of trinitarian doctrine hinders full recovery of the trinitarian insight into the essential relatedness of God. The fatherhood of God should be rethought in light of the critique of feminist theologies and also in view of the nonpatriarchal understanding of divine paternity to be found in some biblical and early theological writings.

Sixth, revising trinitarian theology along soteriological lines raises the question of its place in the dogmatic schema, that is, whether it ought to be treated as a separate "tract," as prolegomenous to theology, as its apex and summary, or as an undergird that is presupposed throughout but never alluded to explicitly.

Seventh, trinitarian theology must be pursued within the context of the "God question" of every age, whether this question takes the form of existentialist atheism, secular humanism, or some other.

Eighth, the Christian doctrine of God must be developed also within the wider purview of other world religions. Trinitarian doctrine cannot be Christomonistic, excluding persons of other faiths from salvation, nor can it surrender its conviction that God is fully present in Christ.

For trinitarian doctrine to be recovered as a vital expression of God's nearness in Christ, theologians must translate into a contemporary idiom the mystery of God's triune love in a way that does justice not only to the testimony of our predecessors but also to the ongoing and ever-new features of God's relationship with a people.


Biblical and Historical Sources

For the New Testament origins of trinitarian doctrine, see the article and bibliography by Franz Josef Schierse, "Die neutestamentliche Trinitätsoffenbarung," in Mysterium Salutis, edited by Johannes Feiner and Magnus Löhrer, vol. 2 (Einsiedeln, 1967), and Arthur W. Wainwright's The Trinity in the New Testament (London, 1962). A standard and nearly complete exposition of patristic and medieval, Greek and Latin trinitarian doctrine is Théodore de Régnon's four-volume Études de théologie positive sur la Sainte Trinité (Paris, 18921898). Organized chronologically and full of helpful textual references is "Trinité," by G. Bardy and A. Michel, in Dictionnaire de théologie catholique (Paris, 1950), vol. 15.2, cols. 15451855. Standard English-language works include George L. Prestige's study of shifting terminology and concepts in early Greek trinitarian theology in God in Patristic Thought, 2d ed. (1952; reprint, London, 1964), J. N. D. Kelly's historical study, Early Christian Doctrines, 5th rev. ed. (New York, 1977), and Edmund J. Fortman's The Triune God (Philadelphia, 1972). Yves Congar's three-volume I Believe in the Holy Spirit (New York, 1983) is more impressionistic but contains many historical gems and a seasoned approach to this vast field.

Theological Works

In Protestant theology, Karl Barth placed the doctrine of the Trinity as a prolegomenon to dogmatic theology in Church Dogmatics, vol. 1, pt. 1 (Edinburgh, 1936). See also Claude Welch's summary of recent Protestant theology in In This Name: The Doctrine of the Trinity in Contemporary Theology (New York, 1952). Trinitarian theology that centers on the cross is represented in Eberhard Jüngel's God as the Mystery of the World (Grand Rapids, Mich., 1983) and Jürgen Moltmann's The Crucified God (New York, 1974). In Catholic theology, Karl Rahner's monograph The Trinity (New York, 1970) summarizes but also seeks to go beyond standard Western trinitarian dogma. Heribert Mühlen's Der heilige Geist als Person, 2d ed. (Münster, 1966) and Una Mystica Persona (Paderborn, 1964) develop a pneumatological and interpersonal analogy of the "immanent" Trinity. Walter Kasper's The God of Jesus Christ (New York, 1984) is a magisterial summary of classical and contemporary trinitarian theology, developed against the backdrop of modern atheism and in light of current studies in Christology. On Orthodox theology, see Vladimir Lossky's The Mystical Theology of the Eastern Church, 2d ed. (Crestwood, N.Y., 1976).

New Sources

Bobrinsky, Boris. The Mystery of the Trinity. Translated by Anthony P. Gythiel. Crestwood, N.Y., 1999.

Boff, Leonard. Holy Trinity, Perfect Community. Translated by Phillip Berryman. Maryknoll, N.Y., 2000.

Butin, Philip Walker. Reformed Ecclesiology: Trinitarian Grace According to Calvin. Princeton, N.J., 1994.

Collins, Paul M. Trinitarian Theology, West and East: Karl Barth, the Cappadocian Fathers, and John Zizioulas. Oxford and New York, 2001.

Davis, Stephen T., Daniel Kendall, and Gerald O'Collins, eds. The Trinity. Oxford and New York, 1999.

Schwöbel, Christoph, and Colin E. Gunton, eds. Persons Divine and Human. Edinburgh, 1991.

Thompson, John. Modern Trinitarian Perspectives. New York, 1994.

Torrance, Thomas Forsyth. The Christian Doctrine of God. Edinburgh, 1996.

Catherine Mowry LaCugna (1987)

Revised Bibliography

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