It is widely acknowledged that the Shepherd of Hermas is a long and diffuse text, full of symbolism and allegorisation, that defies straightforward generic classification or easy analysis of its content. It can appear rambling and repetitive, and it tests the patience of many modern readers, although it seems to have been very popular in antiquity. Topics such as baptism, repentance and the nature of the Church are prominent, but the frequent yet different ways in which they are presented makes it difficult to give a consistent account of what its author sought to convey, or to be confident that his own ideas were consistent and clearly developed. It is therefore no criticism of this fine monograph, given the nature of its subject matter, to say that Grundeken offers no one single thesis about community building in the Shepherd of Hermas, but rather a sequential analysis of different aspects of this topic, any one of which can be read as a self-contained unit. His study reflects patient and meticulous engagement with the primary text, and is carefully documented with reference to a wide range of secondary literature; most pages devote more space to the footnotes than to the main body of the text, so the reader has the clear sense that although in his vision Hermas did not touch the various stones that he saw strewn around the tower, Grundeken has left no stone unturned in drawing on previous scholarship alongside his own careful reading of the text.

Grundeken is interested in what he may reasonably conclude from the text, not in drawing inferences about any external reality that might lie behind it. Thus he begins with the observation that rhetoric plays an important role in the Shepherd of Hermas: the author directly addresses his audience in all three sections of the book (Visions, Mandates and Similitudes), and Grundeken's concern is to establish what may reasonably be said about the ‘constructed community’ that Hermas as author has created. He argues that the text should be considered a literary unity, and that it was likely written sometime between the end of the first century and the middle of the second, in or near Rome, but he is cautious about using it as evidence for any historical community beyond the one that its author constructs.

His analysis considers eleven topics that Hermas addresses, which Grundeken groups together in three broad categories, although those categories are not present as headings in the table of contents. In the first, Grundeken discusses four different topics that bear on the identity of the community: its relationship to Judaism and whether it should be considered Jewish-Christian; its views on the resurrection; the extent to which the community may be considered sectarian; and its attitude to the Roman authorities (which, he argues, was largely one of indifference; confrontations are best avoided, but members of the community should obey God rather than humans if they are forced to choose between them). Then follow two chapters on what Grundeken describes as social aspects of the community: the author's views on the role of women, and on the function of charity. The third cluster of chapters concerns five ritual aspects of community life: baptism and repentance; community meals; the Sunday collection; dancing (and singing); and the holy kiss. It ends with a very short general conclusion in which Grundeken summarises the preceding discussion and finishes (somewhat abruptly) with the statement that ‘The complexity of the interplay between ideal and reality in Hermas’ portrayal of the Christian community in his attempt to build up a community of renewed believers indicates that he was not as “stupid” as some of his more critical interlocutors, like the Shepherd in Sim. 9,12,1, suggest.’

Grundeken's monograph is a model of evidence-based research. Thus, for example, readers may note how he shows just how little evidence may be adduced in support of the frequent description of Hermas as a Jewish-Christian text, or even that the community to which it is addressed drew either on Jewish Scripture or on distinctively Jewish (as opposed to Christianised) ideas or motifs: ‘For Hermas it is not so much the Jewish heritage as the current situation of the church that matters. Hermas’ primary means of expressing the collective vision of the church indicates that he regards it as a community in its own right.’ Yet although there is clearly less evidence for Jewish-Christian presuppositions or outlook than some scholars have supposed, I wonder whether it is quite as absent as Grundeken suggests. Thus, for example, I find the author's reference at Mandate 10, 3, 2 to the person who ἀνομίαν ἐργάζεται, which might be translated as ‘behaves lawlessly’ or possibly ‘practices lawlessness’, to be more suggestive than Grundeken allows, and I wonder if his very brief discussion of terms such as ‘law’ and ‘commandment’ is really enough to support his conclusion that there is insufficient evidence that they would refer to the Jewish Law. Grundeken may be correct, and he gives a salutary warning that conclusions should not simply be presumed. Yet I wonder if this is an example of when his cautious approach sets the bar too high and requires explicit evidence, where implicit evidence, or the reasonable use of inference, arising from a careful analysis of the text, which carefully weighs and balances probabilities, might be enough to support a different view. To conclude that there is little (or even no) evidence to demonstrate that the Shepherd of Hermas was a Jewish-Christian text is one thing; to conclude that it was not a Jewish-Christian text is another.

Also relevant to this question of what a historian may reasonably expect to find in his or her sources is the way in which Grundeken offers a patient and detailed analysis of Hermas's views on resurrection belief, which he summarises as follows: ‘Hermas does not envision a resurrection, an angelic afterlife, or an ascension of the soul to heaven, but a continued existence (Sim. 5, 6–7). For Hermas, God's son is not the risen-one, but the one who was adopted and exalted by God.’ He notes the claim that Hermas would take resurrection belief for granted, but would not refer to it because it would not fit well with his image of the tower, but Grundeken finds this unconvincing. This is a second instance in which some readers may think him unduly cautious, for it must surely be true that any author, especially one addressing a familiar audience, may assume things that he or she does not need to communicate explicitly to his or her audience precisely because it is part of an implicit understanding that they presuppose and share. What Grundeken succeeds in doing, however, is to show how with respect to the resurrection, as with other topics, there is much to be said for focusing on what the evidence of the text can demonstrate, rather than moving too quickly to draw conclusions about what its author might assume on the basis of presuppositions about what he would likely have believed, but cannot be shown to have believed. That is certainly helpful but, as before, it may set a higher burden of proof than may reasonably be required.

This is a careful and balanced treatment of a difficult text. It helps to illuminate certain dimensions of the community that its author constructed or envisioned, and is a model of careful and sober historical analysis. Its lack of a central thread gives the book a somewhat disjointed feel but that reflects the nature of its subject matter. Its careful structure means that readers may dip in easily at points of interest, but the whole remains greater than the sum of its parts. It is a useful resource that may be consulted on particular topics of interest in the company of an authoritative guide to the Shepherd of Hermas, who sets out clearly the reasoning and evidence on which his conclusions are based.