BMCR 2019.01.41

Where Dreams May Come: Incubation Sanctuaries in the Greco-Roman World (2 vols.) Religions in the Graeco-Roman world, 184

Gil H. Renberg, Where Dreams May Come: Incubation Sanctuaries in the Greco-Roman World (2 vols.) Religions in the Graeco-Roman world, 184. Leiden; Boston: Brill, 2017. lxix, 1046. ISBN 9789004299764 $292.00.


Gil Renberg has done the field an incredible service with the publication of this monumental and far-reaching study. In the preface, Renberg states that one of his primary goals is to offer scholars a single resource for ancient incubation across the Near Eastern and Classical worlds (XVI). He has done precisely this with an exhaustive treatment of textual and archaeological evidence for incubation, including quotations of relevant texts in both the original language and in translation, alongside complete publication histories.1

Beyond Renberg’s desire that his book serve as a reference, he is concerned with two key issues: locations and types of incubation. First, he aims not merely to compile all the sites at which scholars have suggested incubation took place, but to evaluate the evidence for each. To that end, he offers conclusions about whether the ancient evidence is sufficient to determine conclusively that any particular site was in fact an incubation sanctuary. Second, Renberg argues that we must distinguish between two distinct types of incubation—divinatory and therapeutic—that were practiced in the ancient world, suggesting that the former was both earlier and more widespread than the latter.

The book is divided into four main sections. The first chapter of the introductory section lays the groundwork for the project by briefly exploring terminology and methodological concerns as well as by offering a history of scholarship. The second introductory chapter surveys the earliest evidence for incubation in the Ancient Near East, Egypt, and Greece. Here, as throughout the book, Renberg considers each source with an eye to clarifying whether it reflects incubation or whether some other ritual experience informed the text. Several conclusions emerge from this chapter: incubation developed in the Ancient Near East long before it appeared in either Egypt or Greece (36), the earliest evidence for incubation shows it to have been primarily an elite phenomenon (63), and divinatory incubation consistently predated therapeutic incubation (77, 105).

The book’s second section assesses evidence for incubation in Greek cults. Renberg begins by surveying architectural remains from Asklepieia at Epidauros, Athens, Pergamon, Kos, Corinth, and Lebena, among other sites. He rejects the presence of a stoa or water source as proof that incubation was practiced in a given sanctuary, absent additional corroborating evidence (148, 163, 166). He ultimately determines that the question of whether incubation was practiced at a particular site cannot be answered on the basis of architecture alone, since no one type of structure was consistently and exclusively used for the ritual. Turning to the written and iconographical evidence for incubation in sanctuaries of Asklepios, Renberg meticulously considers whether incubation was practiced at each site. Intricately linked to this chapter is Appendix I (“Sites Insufficiently, Dubiously or Wrongly Linked to Incubation”), where he considers the evidence for incubation at additional sanctuaries, rejecting many at which some scholars have long assumed incubation took place. One of his work’s key contributions is the critical way that he evaluates evidence typically seen as proof of incubation. For example, Renberg maintains that anatomical votives, such as those found at Corinth, are evidence of healing ascribed to the god, but not of the specific healing method (157). Likewise, he distinguishes between intentional and unintentional incubation, so that references to healing dreams—even in those cases where it is clear that the dream was received within the sanctuary—are not evidence for incubation unless accompanied by additional details that confirm that the dream was deliberately solicited (13–15, 201).

The study of therapeutic incubation at Asklepieia concludes with a detailed account of what a worshipper visiting one of Asklepios’s sanctuaries might expect. This includes what Renberg calls the “two sides to Asklepios the healer,” by which he means that Asklepios was said to have both healed miraculously during dream encounters and to have used the dream encounter as a medical consultation for issuing treatment recommendations (218). Renberg then examines the exact process that would have accompanied incubation, from ritual purity requirements and preliminary sacrifices, to the night spent in the sanctuary, and finally to the dedications that concluded the experience. This discussion is augmented by Appendices V (“The Language of Pre-Incubatory Prayer”), VI (“Dietary Restrictions, Fasting and Incubation”), and VII (“Were the Sexes Separated During Incubation?”), where Renberg considers additional issues related to the way that incubation took place.

Chapters Four and Five conclude the study of Greek cults; they are much shorter and deal with therapeutic incubation at sanctuaries of other gods and with divinatory incubation. Most of the fourth chapter is devoted to therapeutic incubation in the cult of Amphiaraos, whom Renberg calls a “virtual clone of Asklepios” (272). In addition to this connection to Asklepios, Amphiaraos is distinguished by the relatively abundant evidence that survives for his cult at Oropos and, to a lesser degree, Rhamnous. Evidence for the other deities surveyed in this chapter is limited to a single textual reference, and as a result it is difficult to reconstruct precise details or the scope of incubation within their cults (271). While Renberg concludes that therapeutic incubation took place at only a “minority of healing sanctuaries” (309), he contends that divinatory incubation may have been a more extensive form of divination than often imagined (326). However, unlike the Panhellenic cult of Asklepios, divinatory incubation was largely a local phenomenon, with dreams solicited from Pasiphae at Thalamai, Brizo on Delops, Amphilochos at Mallos, and Mopsos at Mopsouhestia. In addition, Renberg discusses the possibility of incubation in several cults of Trojan War heroes and among oracles of the dead.

In the third section of the book, Renberg turns to incubation in Egyptian and Greco-Egyptian cults. In contrast to the section on Greek cults, in which therapeutic incubation and divinatory incubation are treated separately, evidence for both is treated within each chapter on Egyptian cults. The reason for this is simple; among Greek cults, only that of Amphiaraos seems to have included both therapeutic and divinatory incubation, while in Egyptian cults the combination was more frequent (329). The Egyptian divinities most commonly associated with incubation are Sarapis and Isis, whose cults Renberg treats separately since he found no sign that visitors to their sanctuaries sought dreams from both of them at the same time (330, 369). Renberg also takes care in this chapter to differentiate between the textual and material evidence from Egypt and that from elsewhere in the ancient Mediterranean world. He argues that incubation was not as common a means of requesting help from either Sarapis or Isis as has been commonly thought (330–331). Rather, he proposes that while both certainly communicated with worshippers in dreams, there are relatively few examples that definitively meet the criteria for incubation in that they were solicited and that they took place within the confines of a sanctuary (392). Likewise, both are known for healing, but it is not clear to what extent this healing was the result of incubation (393).

Chapter Seven looks at the temple complexes at Saqqâra, located in the region of Memphis. The site housed a number of distinct cults, with abundant evidence in the form of architecture as well as through numerous inscriptions and papyri (398). Yet many questions remain about the extent to which incubation was practiced at Saqqâra. Renberg concludes that definitive evidence for therapeutic incubation only exists for Imhotep (425) and divinatory incubation for Thoth (434–435), although in both cases it is possible that the other type of incubation was also practiced. Neither is clearly attested for Osorapis/Sarapis (413–414) or Isis (445). What remains uncertain, however, is whether anyone other than cult officials would have had sufficient access to the precincts to engage in incubation (446).

Imhotep, together with Amenhotep, is again the subject of inquiry in Chapter Eight, where the focus has shifted from Lower Egypt to the district of Thebes. While both gods were worshiped as healers and while some texts may hint at therapeutic incubation, this cannot be demonstrated conclusively, and limited space within the sanctuary would have precluded large numbers of worshippers from engaging in it at the same time (457, 466). Divinatory incubation, in contrast, is clearly attested for Amenhotep in a single source, but it is unclear whether the practice was common or whether there were other methods of obtaining oracles from him (472). A final chapter in the section on Egypt considers a number of other cults, for which evidence pertaining to incubation is limited to one or two sources (484). Strong support for divinatory incubation exists for Bes at Abydos (496), while significant questions remain about the other cults.

The fourth and final section of the book is a collection of studies that relate in some way to incubation but do not fit directly into the structure of the book’s first three sections. One minor point on the production of the book is in order here. Renberg regularly refers the reader to the material covered in one of these seventeen appendices. It is therefore somewhat confusing to discover that no appendices are listed in the table of contents for either volume. What Renberg calls appendices (and what are indeed labelled as such at the beginning of each), are labeled in the table of contents as “Part 4: Thematic Studies and Catalog.” Of these, Appendix VIII (“Illustrated Catalog of Incubation Reliefs from the Cults of Asklepios and Amphiaraos”) is particularly valuable; in addition to a detailed description and complete bibliography for each relief, it provides an image for all of them, including those only described but missing a plate in LIMC. Appendix XVI (“Incubation in Late Antique Christianity: A Bibliographical Survey and Analysis of the Sources”) is also of significant note. In this lengthy study, Renberg argues that “Christian incubation” is a misleading category, since much of the evidence commonly grouped under this rubric does not pertain to therapeutic dreams explicitly solicited as such, but to “seeking divine aid in whatever form it might come at a holy site while resting or sleeping” (793).

The last comprehensive study on incubation was published in Latin more than a century ago, and this reviewer has no doubt that Renberg’s book will become the standard discussion on the subject for decades to come.2 He has expanded the conversation that can be had about incubation in the ancient Mediterranean world by integrating the Greek and Egyptian material, where previously the boundaries of modern academic disciplines and training precluded scholars from serious engagement with both bodies of evidence. That being said, there is, to a certain degree, tension between the book’s two contributions. On the one hand, Renberg has aggregated a huge quantity of data regarding incubation in the ancient world, and on the other, he attempts to make an argument both about the prevalence of incubation and about the relationship between divinatory and therapeutic incubation. In a book of this length and detail, it should perhaps come as no surprise that at times it is difficult to see the forest for the trees. Nevertheless, Renberg’s critical evaluation of the sources will have an inevitable effect on the way that scholars approach this material. His argument that therapeutic incubation was not as widespread as sometimes suggested and that it must be clearly distinguished from divinatory incubation will change the trajectory of future research.


1. Renberg only provides original texts for sources written in Greek, Latin, and Demotic, which are the bulk of his sources. Texts written in the languages of the Ancient Near East as well as in Coptic have been given in translation only (XX).

2. Deubner, Ludwig. De Incubation capita quattuor. (Leipzig: Teubner, 1900).