The focus of Boersma's monograph is Augustine's departure from the earlier Latin tradition of unequivocally identifying the imago Dei with Christ only, and not the human person. Prior to Augustine, the term imago Dei more or less had to be interpreted to imply equality with God; after Augustine's engagement with Plotinus, the concept of image becomes sufficiently nuanced as to be applied to the human person (p. 166). The genealogy and the theological bases of this development together constitute the focus of the book, which is divided into two main parts. In the first part, Boersma focuses on three particular Latin ‘pro-Nicene’ figures and their influence on Augustine's theology of imago Dei, namely Hilary of Poitiers, Marius Victorinus and Ambrose of Milan. In the second he discusses the novelty of Augustine's approach to this concept, informed especially by a Platonic theory of participation (p. 13), which enabled him to make distinctions his predecessors did not. One of the virtues of Boersma's monograph is how he deftly situates Augustine with respect to his foregoing tradition and context(s) and at the same time demonstrates the novelty and the creativity of Augustine as a thinker.

In the opening pages of the second part, Boersma situates Augustine's understanding of imago within the context of Plotinus’ cosmology, which envisions an asymmetrical participatory structure (p. 147). I was disappointed that Boersma did not spend more time on the concept of participation itself. This is a highly loaded term, and though he did provide some definition, Boersma did not engage with the wide array of literature on this theme. Nonetheless, the important point is that Augustine emphasises the positive sense of image (pp. 180, 203, 206). Whilst image primarily if not exclusively designates something derivative for someone like Victorinus, Augustine looks at how an image can possess being in its own right (p. 203). Image also implies a direct relationship between source and image, and a reflection of the former in the latter (pp. 136, 198–9).

Augustine develops the concept of imago by arguing that an image can participate in its source in different ways (p. 190). For Augustine, x and y can be images, but to different degrees of likeness, or similitudo (p. 165). The key departure is encapsulated in Diu. q. 51.4 (p. 193), in which he reasons that since scripture unequivocally asserts that man is the image of God (e.g. Gen 1:26, 1 Cor 11:7), one must maintain this theological position. However, the uncreated imago is imago simpliciter, whereas man is also said to be created in or ad imaginem. The concept of aequalitas introduces further important nuances into imago (pp. 202, 203, 207). In Diu. q. 74, Augustine states that image entails likeness, but not necessarily aequalitas (p. 194). As Boersma explains, ‘positing that imago may or may not involve aequalitas allows Augustine to affirm what he thinks is the clear meaning of Scripture – namely that the human person is created in the image of God – while still retaining the unique character of Christ as the imago who alone is equal to God’ (p. 202). As in, for example, Epistula 147, the auctoritas of scripture becomes a key driver of Augustine's thought (pp. 192–4, 202).

Boersma does a service to the field by presenting the integral link of the creation of the human person ad imaginem and rationality. Man enjoys a special form of participation in God, namely in the former's intellectual nature (p. 138). The human image pertains to the ‘inner man’, the soul, or reason (pp. 209–10). However, the body is also imago (pp. 218–19). The original integrity of this image is undone by sin (p. 221). In addition to the perception of truth, Boersma rightly notes that Augustine sees judgement as an essential aspect of human rationality (pp. 211, 225, 237–8). A normative element derived from knowledge of the eternal forms serves as the foundation for one's reason.

Boersma also gives great attention to a somewhat neglected point in Augustine's corpus, namely what he describes in terms of ‘transvalutation’ (pp. 166, 170, 189, 225, 232, 235–8, 240, 248, 252–3), or learning to view the world as an image of a greater reality. For Plotinus, the world becomes ‘false’ when one fails to recognise that it is not the source of its own being (p. 149). This theme is likewise crucial for the theories of knowledge of both Ambrose and Augustine. In a word, one becomes what one knows (p. 152). Moreover, the knowledge of the source of one's being partially enables one's return to it (p. 151). In this respect, Boersma dedicates an entire chapter to De uera religione, in which Augustine construes the soul's ascent in terms of recognising the positive sense of imago and what that implies for one's situation in reality (p. 236). However, I was surprised that in his discussion of ascent, no substantive discussion of De libero arbitrio 2 or De sermone Domini in monte appeared. The latter in particular details a path of ascent, couched in the language of the Beatitudes. Despite these critiques, Boersma's excellent work is a major contribution to the field which deserves a wide readership, as it will be helpful to scholars of Augustine and others who deal with early Christianity and late antiquity.