Robert Letham?s book, The Holy Trinity (P&R, 2004) is a superior introduction to Trinitarian theology, certainly the most complete, reliable, and best treatise on the subject to come from a Reformed theologian for I don?t know how long. It covers the biblical bases for the doctrine, provides a long and lucid treatment of the development of the doctrine, and examines recent Trinitarian theology from Barth, Rahner, Moltmann, Pannenberg and Torrance, as well as Bulgakov, Lossky and Staniloae. His grasp of the history of the doctrine is very impressive, and his judgments about various trends and movements are thoughtful and sound. He ends with several chapters on how Trinitarian theology affects our worship and piety, and our understanding of creation and missions (especially with regard to Islam and postmodernism). He discusses the personalism of the Trinitarian worldview, and makes some observations toward a Trinitarian worldview. Letham writes from a conservative Reformed angle, but he is refreshingly open to insights from the likes of Barth and Torrance, and even from Eastern theologians. Many of the chapters end with an example of Trinitarian liturgical literature ?Eprayers and other selections from a wide variety of Eastern and Western liturgies.
There were a couple of minor irritations. At several points, paragraphs are repeated almost verbatim in different parts of the book (e.g., the discussion of creation appears on pp 17-22, and in a very similar form on pages 425-430; he includes a long quotation from Calvin on Gregory of Nazianzen on pages 165 and 378). Letham?s discussion of postmodernism is weak, accepting the worse caricatures and without any citations from postmodernist writers themselves (this is in contrast to his abundant quotations from original sources elsewhere in the book). That said, his basic critique of postmodernism (diversity without unity) is perfectly sensible.
And I have some substantive disagreements, or I do if I have read Letham correctly. He argues for ?icons?Eof the Trinity in the created order, but I wish he would have considered whether divine perichoresis is also reflected in creation (Gunton, eg, suggests that there is a sort of temporal perichoresis in the overlap and interpenetration of past, present, and future). He denies that human beings can indwell one another, since we ?are separate and autonomous personal entities?E(p. 157). Autonomous? What happened to the relational character of God and His creation (man especially) that Letham emphasizes so much (see below)? If we are made in the image of a God who is thoroughly personal/relational, does that at least limit our autonomy? How does this comment square with Letham?s later quotation from Emmanuel Mounier to the effect that the person is a ?living activity of self-creation, of communication and attachment, that grasps and knows itself, in the act, as a movement of becoming personal?E(p. 459). The latter quotation would seem to mean that ?communication and attachment?Ewith OTHERS is essential to the becoming of the self. But then we are not so ?separate and autonomous?Eas Letham suggests.
Along similar lines, he appears somewhat inconsistent with regard to the question of whether or not we enter into the perichoretic fellowship of the Trinity when we are saved. He seems to deny this when he says that perichoresis of the Triune persons is not ?akin to the sense in which God comes into the saints to strengthen them?E it is true, as he goes on to say, that ?the Son is not Son by participation, but by being the Father?s offspring?E(p. 139). In a strong sense of ?akin,?EI would agree; our indwelling in God and His in us is not of the same ?genus?Eas the Father?s indwelling of the Son. Yet, surely there is an analogy (as Letham points elsewhere, though without using the word perichoresis: ?the three indwell the one who loves Jesus,?Ep. 469). I?m happy for Letham to reserve ?perichoresis?Eto the mutual indwelling of the persons within the single substance of God, but, again, I?d like to see more consideration of the possibility of images of perichoresis in creation and redemption.
The valuable parts of the book far outweigh the negatives. Here are a few of the things I found most helpful:
1) One conclusion from his discussion of creation is that ?this God who made the universe . . . is relational. Communion and communication are inherent to his very being. In creating the world, he has made us for himself, to enter into communion with him in a universe of ravishing beauty and ordered variety?E(p. 21). This emphasis on the inherent relationality/personality of the Triune God runs throughout the book. One way it appears much later in the book is in his emphasis on ?union with God?Eas the basic content and goal of salvation (pp. 464ff.). He broadens the point in several places, arguing for a ?relational cosmos?Ethat ?points unmistakably to its relational Creator?E(p. 437).
2) He defends Origen from charges of Christological heresy (pp. 101ff). Elsewhere, he defends Athanasius against charges of Apollinarianism (pp. 130ff), arguing the Athanasius often uses ?body?Eto refer to the whole human person rather than simply the physical body.
3) He provides a cogent overview of post-Nicean controversy, pointing out the confusions of the First Nicene formula, its ambiguous use of ousia and hypostasis, the confusions about homoousios, and the question of the generation of the Son.
4) He is rightly hostile to the Eastern distinction of energies and essence, which he finds already in Basil, who asserts ?that we know the attributes of God . . . , which are in our reach, but that the essence of God (who he is) is beyond us, and so we do not try to approach that?E(pp. 152-53).
5) He quotes LaCugna?s summary of the Cappadocian theology (p. 165): Each person ?is the divine ousia; the divine ousia exists hypostatically, and there is no ousia apart from the hypostases. To exist as God is to be the Father who begets the Son and breathes forth the Spirit.?ESince the persons are defined in the Cappadocian theology by relations of origin, it is ?impossible to think of a divine person ?unto itself,?Edisconnected either from other persons or from the divine essence . . . . it is impossible to think of the divine essence in itself or by itself.?E
6) Letham argues throughout for the ?equal ultimacy?Eof the one and the three, rejecting proposals (Gunton, Bray) to emphasize the persons more and challenging the Western tendency (or what is said to be the Western tendency) to emphasize the one essence at the expense of persons. He says that van Til?s ?one person, three persons?Eformula is confusing, but agrees with van Til?s intention: ?there is no question of God being less than personal?E(p. 462).
7) He gives a persuasive defense of ?only begotten?Eas the proper translation of monogenes (pp. 383-89). One key point is that whenever the word is used to describe God, the emphasis is on the ?spiritual rebirth of believers.?EThis provides the analogy between the Father?s relationship to His ?only begotten?ESon with the birth of ?children?Eof God: ?As God has become the Father of believers in their generation or birth, so the Word stands in relation to the Father as his monogenes?E(p. 385), and ?the invariable connection with spiritual begetting or birth makes it impossible to eliminate any reference to begetting when it comes to the Son?E(p. 387).
8) He provides the most thorough defense I have found of the notion that the Jesus?Esubmission to the Father points to an eternal submission of the eternal Son to the eternal Father (I have not read Barth on this, whom Letham cites repeatedly). He asks, ?Is there something in the Son as Son that makes this union with an obedience human nature fitting??EHe answers, ?If there is nothing about the Son as Son that makes personal union with an obedient human nature appropriate and fitting, then we would be in peril of a Nestorian separation between the Word incarnate, for whom submission to the Father would be inappropriate, and the assumed humanity which does submit to the Father. Such a separation is ruled out by orthodox Christology?E(p. 395). Citing language of the Second Council of Constantinople, he affirms that the humanity of Christ is anhypostatic, while the Word is enhypostatic, concluding that ?all actions of the incarnate Son according to both natures are attributed to the person of the Son . . . . Thus, the Word incarnate obeys the Father. At the same time, it is the Word incarnate who obeys the Father?E(p. 395). The fact that obedient humanity makes a proper ?housing?Efor the eternal Son is grounded in creation. Citing Bulgakov, Letham argues that ?the union of the Word with human nature corresponds with the original relation between them. Man, on his side and for his part, must be capable of receiving and making room for a divine person in place of the human. ?The incarnation thus appears to postulate, on the hypostatic side at least, some original analogy between divine and human personality, which yet does not overthrow all the essential difference between them?E . . . So, Bulgakov concludes, it was natural for the Word to take the place of the human personality of the human nature of Christ?E(p. 396). The image cannot be pressed, but perhaps it is helpful: The Son can become man because the suit fits.
Letham also quotes Barth?s insistence that the Son?s humility has to have a basis in the life of God. ?For God it is just as natural to be lowly as it is to be high,?EBarth argues, so that ?even in the form of a servant, which is the form of his presence and action in Jesus Christ, we have to do with God himself in his true deity.?EIf this were not ?natural?Eto God, then God would be acting in an arbitrary manner. Further, ?if in his proper being as God God can only be unworldly, if he can be the humiliated and lowly and obedience One only in a mode of appearance and not in his proper being, what is the value of the true deity of Christ, what is its value for us??E(p. 397). That is, why insist that Jesus is true God if in fact the humility of His form only obscures the reality of His divinity? He cites Alar Laats, who summarizes Barth?s point by saying ?The basis of the determination of the Son to become a human being and thus the basis of his humility and obedience is in the immanent Trinity. The Son is obedient already antecedently in the Trinity?E(p. 403). Put in those terms, the point is indisputable: The Son is SENT, and obeys the commission of the Father; being that this commission is a commission TO BECOME INCARNATE, this must be obedience by the Eternal Son. Could this be His FIRST act of obedience?
Letham goes on to argue that this submission is not subordinationism, nor does it imply a ?rank?Eor ?hierarchy?Eor a ?chain of command?Ein God. ?Taxis?Eor ?order?Erefers not to hierarchy but ?in the sense of a fitting and suitable disposition?E(p. 400). In an appendix, Letham returns to this point, sharply responding to Gilbert Bilezikian?s critique of Letham?s application of Trinitarian order-in-equality to male-female relations (pp. 479ff).
9) Letham is pretty sharp with evangelical and Reformed treatments of the Trinity (p. 408): ?Charles Hodge plows through some 250 pages on the doctrine of God before turning his attention to the Trinity. Louis Berkhof follows the same pattern ?Epage after page on the existence of God, the knowability of God, the being and attributes of God, and the names of God. Only then does he consider the Trinity. On the more popular level, J.I. Packer?s best-seller Knowing God (1973) has only seven pages out of 254 on the Trinity. He recognizes that for most Christians it is an esoteric mystery to which lip service may be paid once a year on Trinity Sunday. However, after his chapter his over, he carries on as if nothing has happened.?EAnd this in a book that won an endorsement from Packer! Or this, ?Examine any hymnbook or chorus book you can find, and search for compositions that are clearly Trinitarian. You won?t find many. Ask yourself, as you do, how many items could easily be sung by Unitarians, orthodox Jews, or Muslims. You will be surprised?E(p. 410).
10) Letham?s comments on the Trinity and worship are excellent. He cites Basil a few times to the effect that ?the Spirit is frequently spoken of as the place of them that are being sanctified . . . . This is the special and peculiar place of true worship . . . In what place to we offer it? In the Holy Spirit?E(P. 416). Further, he argues (as does Jeff Meyers in The Lord?s Service ) that worship is not first and foremost what we do, but what God does: ?our actions initiated and encompassed by his?E(p. 416). In His own self-offering, Jesus also offers ?his people in him?Eto the Father, thus giving us a share ?in the relation that he has with the Father?E(p. 416).
11) He also quotes Gregory of Nyssa a few times concerning the mutual glorification of the persons of the Trinity: There is ?a revolving circle of glory from like to like. The Son is glorified by the Spirit; the Father is glorified by the Son; again the Son has his glory from the Father; and the Only-begotten thus becomes the glory of the Spirit . . . In like manner . . . faith completes the circle, and glorifies the Son by means of the Spirit, and the Father by means of the Son?E(pp. 418-419). He also notes the Trinitarian structure of Calvin?s doctrine of the Supper: The Father offers us the incarnate Son through the Spirit (p. 423).
12) He challenges the Cappadocian notion that the persons are only distinguished by relations of origin, and he refutes this notion by pointing to the economic revelation of the persons. ?Only the Son became incarnate, not the Father or the Spirit. Only the Holy Spirit came at Pentecost, not the Son or the Father. Only the Father, not the Holy Spirit, sent the Son . . . . . these economic activities point back to immanent relations. If the Incarnation could equally have taken place with the Father or the Holy Spirit as the subject, would God not be arbitrary? We have argued that there is something appropriate in the Son qua Son becoming incarnate?E(p. 418).
13) Letham argues that Trinitarian theology alone supports creatio ex nihilo (p. 432). The main argument seems to be drawn from Irenaeus, who argued that the Father created through His two ?hands,?Ethe Son and Spirit, and thus there was no need for Gnostic emanations. Only two realities thus exist, Creator and creature, and the creation is real only insofar as it is upheld by the two hands of God. This is provocative, but I would love to have seen more development of this argument.
14) He characterizes Calvin?s view of creation as ?semiotic?E(p. 433). Yet, he is agnostic about vestigia trinitatis. He appears to limit the scope of this term to attempts to discover triadic patterns in creation; he admits that there are some stimulating possibilities, but argues that all triads in creation are defective portraits of the Trinity. The clearest revelation of the Trinity in creation are not triadic structures but the ?inescapable and overwhelming evidence of unity in diversity and diversity in unity?E(p. 437). He rightly characterizes Barth?s ?rejection of the vestigia Trinitatis ?Eas a position that ?flows from his programmatic rejection of natural theology?E(p. 437).
15) His trenchant comment on evangelicalism cannot be ignored: ?Evangelicalism was a reaction of Christianity to [the modern] worldview, and in many ways an adaptation to it. While right-wing fundamentalism ignored modernism, evangelicalism took over some of its features, stressing regeneration, sanctification, and evangelism ?Eall good and necessary, but directed to the human end of the gospel, in contrast to the historic faith. The church historically had confessed faith in the Trinity, the incarnation of Christ, and the church and sacraments . . . . the focus of C[onstantinople] ?Ethe Trinity, the Incarnation, the church and sacraments ?Ewas the hard co re of the faith. Evangelicalism, responding to modernism, went down a new and different route, concentrating its energies on matters relating to man and personal salvation?E(pp. 447-448). I would venture to say that many Reformed churches today are subject to the same criticism. The hostile reaction to an emphasis on sacraments and church in recent years is one sign of this capitulation to modernity within the Reformed churches.
16) In the course of discussing union with God and deification, Letham cites a study that finds a doctrine of deification in Calvin (p. 472).
17) He cites Robert Gosseteste?s command on the various dimensions of union that make up Christian faith and practice: ?there seem to be grouped together the following unities or unions: the union by which the incarnate Word is the one Christ, one Christ in his person, God and man; the union by which Christ is one in nature with the church through the human nature he took on; and the union by which the church is reunited with him by a condign taking up, in the sacrament of the Eucharist . . . . These three unions seem to be grouped together in the One who is called the whole Christ . . . [Scripture] adds also the unity of our conformity in the highest kind with the Blessed Trinity, through our reason. To this conformity and Deiformity we are led by the mediator, Christ, God and man, with whom we form one Christ.?EBy no means a perfect statement, but still wonderful.