Pp. xiv, 249 , Oxford University Press , 2007 , £60.00/$110.00 .

From the factions leading up to the Council of Nicaea to the fallout after the publication of Dominus Jesus, the most substantive Christological debates aim to reconcile how God is one and how the man Jesus Christ is God. Jon Robertson's study of how three 4th century theologians made sense of the Christ's unique mediation between the divine and the order of becoming, suitably (yet surprisingly) ending with an insightful look at the failed Christology of Roger Haight. What Eusebius of Caesarea, Marcellus of Ancyra, and St. Athanasius all have in common is a life-long struggle to explain how the incarnate Logos is at once one with the Father as well as one with creation.

To understand these three figures most accurately, however, Robertson opens by taking us back to Origen and his understanding of the Logos as mediator (pp. 11–36). Here Robertson argues that while Origen may have chosen some rather infelicitous phrases to describe the real distinction between the Father and the Son (οθɛοζ and simply θɛοζ), they do nonetheless share a ‘substantial unity’ evidenced by the mutual activity ascribed to them equally within Origen's theological macrostructure.

For Eusebius of Caesarea the Logos is likewise divine yet one also with the created world: ‘for the Logos to function truly as a mediating being it must share something of the two extremes between which it mediates … a relationship of some sort with both God above and creatures below’ (p. 37). This chapter on Eusebius (pp. 37–96) thus opens by focusing on this bridge-character of the Son, and in so doing, Robertson shows how as image the Son is ‘carries’ the Father's likeness inline image, but as begotten the Son was excluded (Robertson's favored term) from univocal identity with God. Or as Eusebius himself would say, the Son cannot co-exist with the Father because the Father pre-exists the Son. In his attempt to safeguard the monotheistic preeminence of the Unbegotten, Eusebius saw no way to relegate the same divine status to the Son. This section concludes with an excellent examination of the ecclesial and political influences as well as the implications of such a position.

Similar to Eusebius, Marcellus likewise wanted to safeguard the monotheism of Christianity by carefully explaining how Christ could be understood to be God as well. Chapter 3 (pp. 97–136) accordingly opens by explaining Eusebius' critique of Marcellus (viz., Contra Marcellum). Eusebius argued that Marcellus erred in making the Logos a mediator only from the moment of the incarnation onward. Yet Marcellus could not admit what he sensed to be an obvious ditheism: God and the Word must be one, there can be only one divine ‘who’, only one hypostasis, in God. Such a monoprosopic stance of course brought other problems onto Marcellus and Robertson carefully shows how this affected his protology, Christology, and soteriology.

The lengthiest of all chapters concerns Athanasius of Alexandria (pp. 137–216) and serves as a topnotch analysis of the great pro-Nicene's thought. Athanasius of course rejects much of the standard usage of mediation hitherto and insists on an ‘inclusive monotheism’ which views the Godhead as a ‘tri-personal unity within whom’. In this way, the mediating Word in history is at once both the Begotten One (‘internal’ to the Godhead) as well as the only possible mediator between the Father and human persons. That is, Athanasius understood how true divine mediation is possible only through one who is also God; an otherwise infinite regress occurs in and we quickly see how one separate from God can never actually manifest but only point to God. An ontologically separate being is simply unable to bring God into union with created persons but would rather act as only one more intermediary between the divine and the human.

To conclude Robertson not only offers fine summaries of these three different theologies of mediation, but shows how Roger Haight's understanding of the Christ as the Symbol of God (Orbis Books, 1999) is an uncritical exhuming of Eusebius. Robertson argues that Haight's position is deictic because, like Eusebius, Haight and others who follow him want to argue for a divine mediator who himself is not intrinsically and inseparably divine. However, it becomes obvious that if God's mediating symbol is not divine, those who come to such a mediator encounter not the divine but another like them who also stands in need of the divine. As such, by the end of this impressive survey, it is clear how Athanasius' position emerges as the most intellectually satisfying and the most doctrinally and liturgically enriching understanding of mediation.