ST102 Key Theologians in Trinitarian History

John Calvin (1509-1564)

A French born reformer, Calvin is noted for basing his views in Scripture. His Institutes of the Christian Religion (Lat 1536; Fr 1539, 1559) provides the fullest and most biblical explanation of the Trinity from the early Reformation period. Organized loosely around the Apostles' and Nicene Creeds, Institutes served on the one side as a catechism (3d ed, 1559) against M. Servetus and other radical Reformers advocating Unitarianism. On the other side, Calvin especially based his teachings on the Bible, contra the papal insistence on the authority (magisterium) of the Roman Catholic Church. While defending biblical and patristic Trinitarianism, Calvin questioned the "eternal generation" of the Son, suggesting that, at best, this is economic language that has been projected analogically to the eternal relations of the Father and the Son.

Peter Abelard (1079-1142)

A popular Scholastic philosopher and theologian. A collection of 19 propositions attributed to him (six of which have Trinitarian implications) was condemned in 1121 and again 1140. Abelard taught an ambiguous if not improper hierarchical view of the Trinity, the Holy Spirit not being of the same substance as the Father and Son, and a God unable to prevent evil. While later writings seem to correct certain teachings, his views on the Trinity appear unsatisfactory.

Novatian (258)

A presbyter in Rome during the Decian persecution (249-50), Novatian insisted that those who recanted of their Christian faith must not be allowed back into the church. While Novatian appears entirely orthodox in his book on the Trinity, his name came to define the separatist movement especially widespread in North Africa that anathematized all those who deny Christ. Though rejected by orthodoxy, Novatianism persisted well into the 5th century. *Augustine argued against it based on Peter's denial three times of Christ, then forgiveness and restoration as head of the church.

Marcion (160)

A wealthy heretic Marcion taught that the God of New Testament was not the God of the Old Testament. The OT God was petty, judgmental, and inferior to the God of the New Testament. According to Marcion, the Gospel was entirely focused on love, to the exclusion of the Law; so much so in fact that anything resembling the Old Testament was to be discarded. This led Marcion to reject the Old Testament and all of the New Testament, except Luke and Paul's letters. Marcion's Christology is strongly Docetic denying true Jesus' full humanity.

Apollinarius of Laodicea (310-390)

Although most of Apollinaris' writings have been lost, those that remain have come down under the false names of other orthodox writers or in *Gregory of Nyssa's Antirrheticus. He became Bishop of Laodicea around 360, was good friends with *Athanasius, and opposed *Arianism. Although the fragmentary na- ture of his remaining writings makes interpretation difficult, it can be seen that in an ef- fort to stress the unchangeableness of the Logos (Christ), he denied that Christ had a ful- ly human mind. This would imply that Christ was not complete in his humanity and therefore incapable of fully redeeming and healing all that is human.

Hilary of Poitiers (315-367)

Appointed Bishop of Poitiers around 350, Hilary was the first theologian in the West to complete a work on the Trinity (De Trinitate). Earlier he was banished from his bishopric for four years and during his exile he was introduced to Eastern thought on the Trinity, specifically the debate regarding homoousios (of the same substance) versus homoiousios (of similar substance). He advocated a mediating position that simultaneously maintained the full divinity of Christ and the Son's distinction from the Father. Hilary points toward perichoresis and the full deity of the Spirit, yet he does not explicitly articulate either.

Irenaeus (130-200)

As Bishop of Lyon and seeking to pastorally care for his people, Irenaeus came into sharp dispute with the Gnostics (who denied Christ's humanity). He em- phasized traditional Christian elements like the Church, Baptism, and Scripture. Theologically he defended all three members of the Trinity (without using that word) as being divine and eternal yet still distinct: "there is declared one God, the Father, uncreated, invisible, maker of all things, above whom is not other God whatever...And God is rational, and therefore produced creatures by his Word, and God is a spirit, and so fashioned everything by his Spirit"(Ancient Christian Writers, 49). Irenaeus also suggested (as Justin Martyr) that Mary functions as the New Eve, just as Jesus is the Last Adam. He is called the father of Christian theology.

Justin Martyr (100-165)

As with the other Apologists, Justin's chief aim was to defend the faith against the prevailing animosity toward Christianity both by Jews (Trypho) and pagans. As a trained philosopher Justin was the first Christian to use Aristotelian categories in attempting to prove that Christianity was in fact the true and supreme philosophy. Justin developed a Logos theology (the Word latent and coming forth from God) in Apologies and Dialogue with Trypho the Jew.

Karl Barth (1886-1968)

Barth is often considered the greatest Protestant theologian of the 20th century. Arising out of the crisis of WWI, Barth is best known for challenging the preva- lent liberal, non-Trinitarian theology that dominated theology from *Schleiermacher onward. Barth's massive Church Dogmatics reaffirms a form of historic Trinitarian orthodoxy with God as the Revealer, Revealed, and Revealedness; God self-manifests as unimpaired in unity yet also unimpaired in differentiation (I. 339). Rather than the term persons, Barth prefered to speak of three modes of existence—although he seems innocent of classical modalism. Barth insisted that the Bible is the foundation of Trinitarian dogma, albeit only implicitly. His strong classical view of the Incarnation of the Word reaffirmed traditional categories of enhypostasis and anhypostasis. Later 20th century theologians have sometimes credited Barth with the beginning of a renaissance of Trinitarian thought, including elements of a social Trinitarianism.

Alexander of Alexandria (328)

Bishop of Alexandria from 312 to 328, most famous for being the bishop who articulated the doctrine of the Trinity while excommunicating *Arius. In both his episcopate and as a leading member of the Council of Nicaea, he affirmed the eternality and homouousios of the Son with the Father. He named *Athanasius as his successor.

Theophilus of Antioch (later 2 century)

Bishop of Antioch and Christian apologist, with Apology (3 vols) surviving as his presentation of the Christian God against the immoral myths of pagan Greco-Roman gods. He spoke of the Logos as the internal intelligence of the Father who was brought forth to create all else. The term "Triad" (triavß) for the Godhead is first found in Theophilus. The Spirit is seen primarily as prophetic actions.

Maximus the Confessor (580-662)

Born into Byzantine aristocracy, Maximus became a monk in c. 614. A prolific writer, some 90 of his works remain, he is best known for defense of Christ's two wills (divine and human). He argued that the two wills were not at odds but both were clearly on display in the life of Christ. His style is a brilliant synthesis of Eastern and Western thought and clearly defends the unity and diversity within the Trinity. He used the term perichoresis both for the internal relationship of Christ's two natures and for the Trinitarian relations.

Thomas F. Torrance (1913-2007)

Born of missionary parents in western China, later with many international engagements (condemned to death in Iraq!, etc.) Torrance became longtime professor of dogmatics at the University of Edinburgh. He is known for his work on the relation of theology and science, and equally his careful scholarship regarding Christology and the Trinity: The Trinitarian Faith (1988), Trinitarian Perspectives (1994), and The Christian Doctrine of God (1996). He greatly expanded the acceptance of Cappadocian Trinitarianism in the West, such that his Trinitarian thinking is today perhaps the most respected of any 20th-century Trinitarian writer. His influence is wide, including in his efforts to reunify Reformed, Eastern Orthodox, Lutheran and Roman Catholic traditions.

Augustine of Hippo (354-430)

Born to a pagan father and Christian mother (Monica), Augustine was a catechumem in childhood. In adolescence he abandoned Christianity for philosophic religion (Manichaeism) and a lover with whom he lived for 15 years and sired a son. He converted under Ambrose of Milan in 386 (Confessions). His writings in general (e.g., The City of God, On Christian Doctrine) and specifically his work The Trinity continue to influence Christian theology worldwide. De Trinitate (399-420) presents various tripartite analogies—primarily psychological but also social (Lover-Beloved-Love itself)— to affirm the reasonability of the one substance of God existing in three subsistent relations. Augustine begins with the unity of God, then to expound the three "ways of being" or (for lack of a better term) "persons." His view of the Holy Spirit as the love be- tween the Father and the Son previsioned the Western addition of the filioque clause to the Nicene Creed at the 3rd Council of Toledo in 589. Prior to Augustine, the emphasis in Trinitarian discussion tended to be on the ontological primacy of the Father, but Augus- tine placed the emphasis on the divine nature and subsistent personal relations—a pattern that until recently dominated Western theology.

Colin Gunton (1941-2003)

British churchman and professor at King's College, University of London, Gunton wrote extensively on what is often termed the social Trinity, locating the unity of God in the perichoretic divine relations. In his Bampton Lectures at Oxford, he famously argued that the Trinity is the ontological key to the problem of unity and diversity in the universe (The One, the Three, and the Many, 1993); The Triune Creator, 1998; and Father, Son and Holy Spirit, 2003.

Athanasius (295-373)

Champion of the doctrine of the Trinity. Athanasius received a classical education and was ordained as a deacon in 318. Most likely in his early twenties, he wrote his famous On the Incarnation that against Arianism articulates the equality of the Son with the Father. Although relatively young, he actively participated at the Council of Nicaea (325) and was soon appointed Bishop of Alexandria (328). The years that followed were a constant struggle through several exiles to uphold orthodoxy against a revived Arianism empowered by emperors and opposing bishops. Under his leadership with *Basil of Caesaria, the Council of Alexandria (362) brought clarification of the terms hypostasis (as "person") and ousia ("substance"), thus increasing understanding between the Eastern and Western fathers. To Athanasius is attributed the first full listing of the NT canon (367) and the biography Life of St. Antony that popularized monasticism throughout Christendom.

Gregory of Nazianzus (330-390)

Close friends with *Basil and his younger brother *Gregory of Nyssa, Gregory Nazianzen is the "middle" member of the Cappadocian Fathers, and sometimes termed "the Theologian." Born into a Christian family, he was ordained a priest in c. 362. Owing to his eloquent preaching, he helped restore Constantinople to Nicene faith and presided over the initial part of the Council of Constantinople in 381 (appointed Bishop of Constantinople at the same time), but Gregory resigned and left because of rancor against him. Theologically Gregory sought to reconcile strict monotheism with the three "persons" (as Basil, hypostases or prosopon). Again the Son and the Spirit were seen as proceeding from the arche of the Father. Yet "one is not more God, the other is not less God; one is not before, the other after. They are not divided in will or separated in power... To put it in one word, the divinity is undivided in those who are divided" (Orat. 5; also On the Holy Spirit, 14). Gregory once used the term perichoresis to depict union of Christ's two natures, a theme developed later by *Maximus and *John of Damascus. He also led in the anathematization of Apollinarius at the Council.

Athenagoras (2nd century)

Described as "the Christian philosopher of Athens," Athenagoras is known for his letters (A.D. 176-180) to Emperors Marcus Aurelius and his son Commodus that defend Christian faith against popular criticism. An astute apologist, Athenagoras countered three main charges against ancient Christians: incest (because they called each other brother and sister), cannibalism (owing to the Eucharist), and atheism (because they rejected the Roman pantheon). On this final point, he explicitly identifies the Christian God as the Father, Son, and Holy Spirit, one in power and diverse in rank.

Jürgen Moltmann (1926- )

Drafted into the German army at the end of World War II, Moltmann was captured and in prisoner-of-war camps converted to Christian faith. After academic training and stimulated by dialogue with Marxists and progressive Catholics, he concluded that eschatological hope must be the center of Christian theology (Theology of Hope, 1964). A decade later Moltmann initiated a broad movement of social Trinitarianism that emphasized the primacy of the divine personal relationships and the engagement of the triune God with the world in solidarity with human suffering (The Crucified God, 1974; The Trinity and the Kingdom, 1980). Moltmann ties Trinitarian identity to salvation history in such a way that God necessarily finds self-authentification and fulfillment in human and cosmic history culminating in the eschaton when God becomes all in all. Not surprisingly, if God is codependent on creation, many judge Moltmann's theology as finally pantheistic. Eschewing systematization of theology, Moltmann is marked by creativity and synthesis of theological, ethical, and political concerns—albeit often highly speculative and distant from Scripture.

Cyril of Alexandria (444)

Elected to replace his uncle as the Patriarch of Alexandria in 412, Cyril became noted for his powerful, sometimes ruthless, exercise of power. Regarding Christology, Cyril is best known for his outline of the one-person/two-nature Christology. His zeal turned against *Nestorius' reluctance to use the term theotokos (God-bearer) of the Virgin Mary, preferring Christotokos (Christ-bearer). Cyril vigorously pursued the condemnation of Nestorius (Patriarch of Constantinople), securing his anathema finally at the Third Ecumenical Council of Ephesus (431), where Cyril himself assumed control. Nevertheless, Cyril brilliantly built upon the Alexandrian theology of Athanasius and that of the Cappadocians and did much to define the trajectory of Christology in subsequent Ecumenical Councils at Chalcedonian(451) and Constantiple II (553).

Origen (185-254)

Extraordinary scholar from Alexandria, Origen was immensely prolific writing both biblical commentaries and theological works—albeit most have been lost owing to his later ecclesial condemnation. The most important enduring work is an unreliable translation of De Principiis. His Platonic influences are well known, as are his threefold hermeneutic (literal, moral, allegorical/mystical) and his rigorously ascetic lifestyle. While affirming the eternal pre-existence of the Son, Origen portrays the Son as one reflective of but less than God the Father. Despite shortcomings he left Trinitarianism with such terms such as "the eternal generation" of the Son, and possibly hypostasis, ousia, theanthropos, and homoousios.

Eusebius of Caesarea (265-340)

Famous for his excellent work on the early history of the church, his thoughts on the Trinity are less than orthodox. He espoused a form of Arianism, while not agreeing with Arianism's most extreme statements. Eusebius did teach the preexistence of Christ but denied the Son's co-eternality because the Son was begotten of the Father. He also affirmed a highly hierarchical view of the Trinity, ultimately viewing the Holy Spirit as a creation of the Son.

Gregory of Palamas (1296-1359)

Forceful advocate of Hesychasm, Gregory's writings have a distinct mystical flavor to them. He distinguished between God's essence and the divine energies. While God remains unknowable, his divine energies permeate everything and can be experienced by humanity in theosis (divinization), similar to many Eastern fathers. He stressed the complete unity of body and soul thus allowing man's physical ac- tivities to have spiritual import. The Hesychastic Prayer combines breathing, bodily rhythm with repetitious prayer to experience oneness with God: "Lord Jesus Christ, Son of God, have mercy on me [a sinner]."

Anselm of Canterbury (1033-1109)

From northern Italy, young Anselm traveled over the Alps into France and was persuaded to take monastic vows at the monastic school at Bec. He later became prior at Bec and traveled on occasion to Canterbury where he was, somewhat unwillingly, made archbishop (1093). Credited with being the most luminous mind between *Augustine and *Thomas Aquinas, Anselm is noted for his almost exclu- sive use of intellectual reason instead of scriptural or patristic authorities. His works on Christology—On the Incarnate Word and most famously Cur Deus Homo (Why Did God Be- come Man?)—yoked the two natures of Christ with satisfaction theory of atonement. An- selm developed the ontological argument for God's existence (Prologion) and defended the doctrine of the Trinity against tri-theistic views and conversely against Islam.

Ignatius of Antioch (35-107)

Ignatius wrote seven letters to various churches across Asia Minor while on his way to be martyred in Rome. Besides his passionate example and devotional value, Ignatius' chief and early contribution to Trinitarian thought was his defense of the divine Christ's humanity and the reality of Christ's suffering against the Docetists.

Montanus (mid to late 2nd century)

In Phrygia of central Asia Minor, Montanus initiated an apocalyptic movement characterized by speaking in tongues, prophecy, fasting, and sacrifice in the expectation of the Spirit's outpouring on the church. He taught that the Heavenly Jerusalem would descend on his hometown of Pepuza. Some sources allege that Montanus claimed himself to be the mouthpiece of the Spirit. Closely accompanied by prophetesses Priscilla and Maximilla, Montanus insisted on a high degree of ethical rigor and charged the wider Christian church with carnality. Although Tertullian became its famous convert, Montanism was condemned before A.D. 200 in Asia and slightly later by Rome.

Nestorius (381-451)

In an effort to defend the distinct humanity of Christ, Bishop of Constantinople Nestorius preferred the term Christotokos (mother of Christ) to the more widely used Theotokos (mother of God). His opponents (notably *Cyril of Alexandria) took this to mean that Nestorius advocated not only two natures but also two persons in Christ. It is unclear if Nestorius actually taught this, but both he and the view that came to bear his name were condemned at the Council of Ephesus in 431. Nevertheless, many in the Eastern church favored Nestorius and even today this empathy marks the (Assyrian) Church of the East. Ironically, his intuition on the dangers of the phrase "Mother of God" proved justified as Mary was elevated to near divine status and Islam completely confused its intended Chalcedonian meaning.

Friedrich Schleiermacher (1768-1834)

Influenced by Immanuel Kant, Schleiermacher reinterpreted the essence of Christian faith as the gefühl or feeling of filial dependency upon God. While the example of such filial dependency is best seen in Jesus, such a salvific experience is universal and transcends religious paradigms. In The Christian Faith (2d ed, 1830), Schleiermacher reinterpret but does not have a divine nature. Trinity is the Christian expression of a threefold experience of God as Father, Brother, and Spirit—thus a secondary theological construct within tradition; but Trinity cannot be said to describe God in himself. Even Schleiermacher's "fatherhood" of God may fall short of any truly personal, relational divine being. Thus, subsequent to several appendixes, "The Divine Trinity" is a phenomenological derivation in theology and placed as the Conclusion to The Christian Faith (¶170).

Catherine of Siena (1347-1380)

Joining the Dominican order, she was the 23rd of 25 children of a prosperous dyer in Seina, Italy. Catherine spent long hours in prayer and mortification. After three years of solitude, she heard Christ's call to the poor and sick and to seek the conversion of sinners. Her attractive personality and extraordinary piety gained her significant influence in affairs of church and state. A collection of her teaching and prayers, The Dialogue repeatedly expresses her mystical devotion to the Cross of Christ and the Holy Trinity: "You have gifted me with power from yourself, eternal Father, and my understanding with your wisdom—such wisdom as is proper to your only-begotten Son; and the Holy Spirit, who proceeds from you and from your Son, has given me a will, and so I am able to love." (Dialogue, in M. O'Carroll, Trinitas, 62). The Great Schism of the Catholic Church contributed to her early grave at the age of 33.

Martin Luther (1483-1546)

Luther is often considered the founder of the Reformation in 1517. As with *Calvin, the doctrine of the Trinity was not at issue between Roman Catholicism and what became known as Lutheranism. Luther insists, however, that Christian teaching must ground not on the authority of *Augustine or *Peter Lombard but the Bible. Interestingly, Luther himself rejected the distinction between person and nature as a "frivolous philosophical invention." Nevertheless, Luther's 50 volume Works (while without a specific exposition on the Godhead) is peppered with references to the Holy Trinity. Thanks to Melancthon classical Lutheranism has not wavered in commitment to the doctrine of the Godhead.

Marcellus of Ancyra (280-374)

Marcellus was an ardent opponent of Arianism and a strong supporter of homoousion language at the Council of Nicaea. In order to defend the unity of God, Marcellus taught that the Son and Spirit emerged from God as distinct entities for the purposes of creation of redemption and will be absorbed back into God after all redemptive work is completed. The phrase 'whose (Christ's) Kingdom shall have no end' was added to combat this teaching.

Peter Lombard (1100-1160)

Most famous for his four volume Sentences, which would become the standard theological textbook for 400 years, Lombard drew heavily from *Augustine and *Hilary of Poitiers. His doctrine of the Trinity takes the unity of God's essence as its starting point. Because of this strong emphasis on the divine substance, Lombard's Sentences was attacked by Joachim of Fiore (a quaternity?) and *Richard of St. Victor, but Lombard's teachings were upheld at the Fourth Lateran Council in 1215.

Arius (260-336)

Most likely born in Libya, Arius was ordained and put in charge of Baucalis, a major church in Alexandria around 312. Noted for his eloquent preaching and asceticism, he advocated the inferiority ("subordination") of the Son to the Father, that is, that the Logos is the first creation of God through whom he created all else. Probably not original with Arius, his teaching gained sympathy with Eusebius of Nicomedia and others. Arius argued that the Son and the Father were not of the same divine essence and that the Son was not coeternal with the Father. Arius' teaching was condemned at the Council of Nicaea in 325. Nevertheless Arius and Arianism were at times reinstated owing to local and imperial whim until the Council of Constantinople in 381.

Rudolph Bultmann (1884-1976)

New Testament scholar and theologian famous for his program of demythologizing the New Testament. In his effort to translate Christianity into modernity (via Heidegger's existentialism), Bultmann drove a wedge between objective history and religious faith. Beyond most other Neo-orthodox (or existential) theologians, Bultmann's radical textual criticism together with his ardent personalization of the Cross-event largely reduced the Christian experience to an individual's death to non- being and rebirth to new life. Bultmann explicitly denied the deity of Christ and Trinity. Whether a person's encounter with God in Christ was in fact an experience of God or whether it was ultimately only an existential crisis of self-authentification is unclear.

Basil "the Great" of Caesarea (330-379)

One of the three Cappadocian Fathers, along with his brother *Gregory of Nyssa and friend *Gregory of Nazianzus, Basil received an education in the best of both Christian (Alexandria) and classical (Athens) culture. He rejected a life of wealth for the monastery and spent his life in the powerful defense of Nicene or- thodoxy. Although not quite explicitly stating the Holy Spirit is God, Basil is most famous for his defense of the Spirit's divinity (On the Holy Spirit) and the refinement of the terms "essence" and "personhood" to say that God is one in essence and three in persons. In particular (correcting *Athanasius' earlier "hypostasis is ousia"), Basil clarified three hypostases as distinct persons of the one essence (ousia) held in common in the Godhead—the language chosen at the Council of Constantinople in 381.

Richard of St. Victor (1173)

Originally born in Scotland, Richard became Prior of St. Victor in Paris. His theology is influenced by *Augustine and *Anselm and a key point of his teaching on the Trinity centers on love. From a rationalist perspective, Richard argues that because God is charity (love), therefore divine charity must be directed toward another equal person or it is not charity. Therefore, at least two equal, divine persons share that mutual love in the Trinity. Richard in this sense is a Western social Trinitarian.

Photius (810-895)

Patriarch of Constantinople. Although not without dispute, most of Photius' writings center on opposition to the filioque; he bases his opposition on the assumption that certain attributes are not shared between the hypostases. He took the procession of the Spirit to be an unshared attribute further claiming that a shared procession (from the Father and the Son) devalues the role of the Father in the Trinity. While by no means the only source of conflict between Greek and Latin Christianity, Photius' posi- tion became increasingly inflammatory making reunion with Rome much more difficult.

Vladimir Lossky (1903-1958)

Perhaps the leading 20th-century Russian Orthodox theologian, Lossky is best known for his explanation of Orthodox thought to the Western world, most clearly in The Mystical Theology of the Eastern Church and The Image and Likeness of God. Lossky stressed the mystical (apophatic) transcendence of God, knowable only through the divine economy in the Son and the Spirit. The Father is the principle of uni- ty in the Godhead, the Origin and eternal Sustainer of the Son and Spirit: "The Father is the cause of their equality with himself" (Image and Likeness, 84). Thus, Lossky insisted on the rejection of the Filioque. Strong advocate of theosis, Lossky was instrumental in the resurgence of work on *Gregory of Palamas (divine energies) and the doctrine of theosis.

Boethius (480-524)

Principally a logician, he is noted for the application of Aristotelian logic to Trinitarian concerns. His definition of person as an "individual substance of a rational nature" has dominated Western thought. Quoted numerous times by *Aquinas, it could be said Boethius thought like a Scholastic long before Scholasticism.

John of Damascus (655-750)

Raised in affluence and holding a high position in the court of the Caliph in Damascus, John resigned (c. 725) to take vows as a monk at the monastery of St. Sabas near Jerusalem. His magnum opus The Fount of Wisdom divides into three sections on philosophy, heresy, and the Orthodox Faith (De Fide Orthodoxa), the latter a compendium of Eastern theology often recognized as the capstone of patristic theology. For John, the Father (arche) is the only source/cause in the Trinity, the eternal Begetter of the Son and from whom the Spirit eternally proceeds. Through perichoresis, the Spirit comes from the Father through the Son and is poured out in and through him. John argued extensively for icons as symbols of the unity of God and creation (theosis) and against the Latin filioque as disruptive of the divine unity in the Father.

Ambrose of Milan (337-397)

Son of the Prefect of Gaul (Trier) and himself a governor in northern Italy, Ambrose by popular demand was baptized and made bishop of Milan in 374. Classically trained and eloquent in the pulpit, Ambrose was instrumental in Augus- tine's conversion (386) and demonstrated remarkable influence with successive emper- ors, notably Theodosius I (who outlawed paganism). His fluency in Greek helped make the Eastern fathers' writings known in the West. He popularized monasticism, Marian devotion, and hymnody. Against Arianism, he was a staunch defender of the doctrine of the Trinity (De fide; The Holy Spirit; The Sacrament of the Incarnation of the Lord). Ambrose is included as one of four doctors of the Latin Church.

John Paul II (Karol Józef Wojtyla, 1920-2005)

The most popular, most traveled (129 countries) and long-tenured (1978-2005) pope of the 20th century, John Paul II was emphatically a Trinitarian theologian, articulating both the consubstantiality of the Godhead while also the distinct roles and practical ramifications of God as Father, Son, and Holy Spirit. Carefully nuanced in relation to other world religions (Judaism and Islam), and again in terms of family life, John Paul's Trinitarian writings are found throughout his many works. With Joseph Cardinal Ratzinger (now Benedict XVI), The Catechism of the Catholic Church was revised in 1995 with Part One (pp. 17-299) a dogmatic exposition of the Apostles' Creed; a popular synthesis was published as the Compendium in 2006.

Karl Rahner (1904-1984)

Though focusing little attention on the doctrine of the Trinity per se, "Rahner's Rule" states that "The 'economic' Trinity is the 'immanent' Trinity and the 'immanent' Trinity is the 'economic' Trinity" (The Trinity, 1967; 2d ed. 1997) 22. The question regarding Rahner's Rule is whether the transcendent God is exhaustively revealed in the economic Trinity; all classical Christianity responds no. Nor is Rahner's phrase adequately elaborated in his own writings. While all agree that the eternal Trinity is truthfully revealed to creation, the degree of the identity between the immanent and the economic Trinity is taken by some recent theologians to be denote absolute identity, even to the point to where God only becomes fully Trinity within the history of salvation (*Moltmann; T. Peters). Rahner also advocated moving away from the language of "person" to "ways of being," but this has not gained acceptance.

Tertullian (155-220)

Trained as a lawyer and converted sometime before 197, the North African Tertullian is noted for his polemical, acerbic style that permeates his writings. His most famous work Against Praxeas articulates an understanding of the Trinity against Modalism and Patripassionism (the view that the Father suffered on the Cross). Several of Tertullian's phrases became permanent markers of Trinitarian orthodoxy: "one substance in three persons"; "God from God, Light from Light"; "the Father is God, the Son is God and the Holy Spirit is God, and each is God" (Adv. Praxean 12). Yet Tertullian opined that the Son/Logos came forth from God, such that the Father was not always the Father. He argued strongly against *Marcion and Gnosticism; at the same time, Tertullian is Montanism's most famous convert.

Thomas Aquinas (1225-1274)

Youngest son of an aristocratic family, at five Thomas was given to the Church. He studied in the Dominican order under Albertus Magnus, mastering an Aristotelian approach to truth. Between Paris and Italy, Thomas lectured and wrote profusely including Summa contra Gentiles and later Summa Theologiae. While recognizing the primacy of revelation, Thomas accorded natural reason a certain autonomy. Valid reasoning begins with sense perception of facts within the natural world. From this he developed his proofs for the existence of God, who is pure act (i.e., perfection realized). Conversely, sacred doctrine is grounded in divine revelation in Scripture and the magisterium; special revelation is essential to ultimate truth understanding of Trinity, and salvation. Central to divine revelation is the Trinity and the Incarnate Word. Like Peter Lombard, Thomas begins with exposition of the divine nature (attributes), then addresses the three persons to which he gives considerable attention. Although vigorously op- posed for decades, Thomas' system of thought revived especially in the 16th century when he was declared Doctor of the Church (1567).

Gregory of Nyssa (331-395)

he final member of the Cappadocian Fathers, he was the younger brother of *Basil and friend of *Gregory of Nazianzus. He was appointed Bishop of Nyssa in 371, then exiled by Arians, returning in 378. Emperor Theodosius I charged him with promoting Nicene orthodoxy in Asia Minor. A gifted philosopher, theologian, and rhetorician, Gregory is best known for his use of philosophic means to defend the Trinity, notwithstanding mystical (apophatic) elements as well. He was heavily influenced by Platonism and unafraid to use it in his writings on the Trinity. He elaborated distinctions between the eternal generation of the Son and eternal procession of the Spirit. Yet he also compares the Trinity to three torches, the first imparting light to the second, then through the second to the third. Gregory defended the notion that Christ was truly two natures in one person, thus implying that Mary is the theotokos.