McGrath, The Only True God: A Book Review

James F. McGrath, The Only True God: Early Christian Monotheism in Its Jewish Context

[With thanks to the author for a review copy]

McGrath’s book has an argument that for many would seem counterintuitive, that the early Christians did not diverge from Jewish monotheism, even despite their veneration of Jesus. For McGrath this is simply because the modern conceptions of monotheism are not how 1st Century Jews would have defined their monotheism.  The book’s thesis is that while Christians, post Nicaea, are used to thinking about monotheism in terms of ontology, 1st Century Jews defined their devotion to the one God in terms of worship.  While Christians did worship Christ in some respects, McGrath argues that only sacrificial worship to Christ would have made Christ equal to God in a way that would constitute a breach of 1st Century Jewish monotheism.

The book itself has the rare virtue of being blessedly short, a mere 104 pages of text (not including notes, bibliography and index).  That being the case, what McGrath achieves within those pages is all the more impressive.  The book is intended to be accessible to those without a detailed knowledge of the field.  Thus the first chapter takes pains to explain clearly the important concepts and relevant methods.  This is done in a thorough but economical style.  In the second chapter McGrath turns to the question of how Jews in the Greco-Roman era would have understood their own monotheism in the context of a world where the worship of many gods was commonplace.  Given the book’s intention to be accessible to the non-expert it is a shame that some of the more obscure source passages referenced, e.g. Hecataeus of Abdera, do not appear in translation, instead the reader is reliant on McGrath’s précis of the relevant points.  Having established a working definition of 1st Century Jewish monotheism McGrath moves on to examine the writings of Paul (chp 3), the Gospel of John (chp 4), and Revelation (chp 5), against this definition.  In each chapter McGrath continues to develop his thesis and in each case finds the Christian elevation of Christ to be within the bounds of his definition of 1st Century Jewish monotheism.

The sixth chapter moves on from the Biblical material to discuss the “two powers heresy” within rabbinic literature.  McGrath argues that after the destruction of the Jerusalem Temple Jewish monotheism was forced to redefine itself.  One result of this process was the rabbinic response to the two powers heresy which while probably originally targeted at the Gnostics came to encompass the Christians also.  McGrath concludes that certain ideas that were condemned in the late 2nd and early 3rd centuries need not have been controversial in the 1st century.  Thus the schism between Christianity and Judaism over their respective understandings of monotheism is re-dated from the 1st to the 3rd century and, surprisingly, is a result of a change in the boundaries of Jewish monotheism rather than a developing Trinitarianism.  The final chapter briefly summarises the book’s findings and then offers some thoughts on their historical and theological implications.

McGrath’s book is excellently written, the only hindrance to the reader’s enjoyment being the use of endnotes instead of footnotes.  It consistently progresses through his argument with nuance but without wasting space on peripheral issues.  It engages with other scholarship in a respectful but efficient manner and represents a significant contribution to the field.  McGrath’s concluding thoughts are balanced and show a concern for further discussion and for the appropriation of the work by theologians.  I would suggest it is essential reading for anyone interested in NT background, Christology, or the historical development of Trinitarian theology.