This short book aims to compare the three groups mentioned in the title, philosophers, Jews and Christians of the first and second century ce, from the point of view of their use of texts, that is, the texts they consider authoritative for them. The idea that guides the narrative of the book is that all three groups make up textual communities, that is, communities sharing, discussing and interpreting certain authoritative texts, and that their reading of the texts contributes essentially to the shaping of their group identity. The book aims to identify common strategies and common aims among the three groups in the treatment of their corresponding authoritative texts and to compare them from this point of view.

The first chapter introduces the topic and the aims of the book, in which the notion of ‘textual community’ is also discussed. The second chapter on philosophers is too short to do justice to a rich and extremely varied philosophical scenery. Science and philosophy flourish especially in the second century ce, and this is clearly part of a more general flourishment of letters and education, as is evidenced in events such as the foundation of the Athenaeum by Hadrian in 123 as a place of education in the artes liberales and the establishment of four chairs of philosophy in Rome by Marcus Aurelius in 176 ce. There is a plethora of important philosophers active in this century: Platonists such as Plutarch, Numenius, Atticus, Apuleius, Taurus, Severus; Peripatetics such as Aspasius, Adrastus, Sosigenes, Aristocles, Alexander of Aphrodisias; Stoics like Marcus Aurelius; Epicureans like Diogenes of Oinoanda; and also sceptics such as Favorinus and Sextus Empiricus. K. speaks instead only of Stoics, Pythagoreans and Platonists. This looks like a random choice. It is true that Pythagoreanism and Platonism loom large at the time, with many neo-Pythagorean writings being produced. But it is also true that many Pythagorean philosophers of the time are not just Pythagoreans but also Platonists, for example Eudorus, Moderatus and Numenius. The reason for that phenomenon has to do with the texts that these philosophers regard as authoritative. All of them consider the Timaeus as the most central work of Plato, which, however, they take to transmit Pythagorean wisdom – Numenius argues explicitly that Plato appropriated the doctrines of Pythagoras (fr. 24.56–62). The important point is the construction of authority within a textual community. For philosophers like Numenius the text of the Timaeus is an authoritative text because it communicates ideas of an authority other than its author. Some of the Pythagorean texts of that time were written in order to credit Pythagoras with widely approved philosophical views from other traditions, such as that of the Categories of Aristotle. K. does not discuss how a text becomes authoritative. One possibility is its attribution to an authority, such as Pythagoras, Plato or Moses. Another, more complex, scenario is the attribution to an authority of widely approved views, that is, of authoritative views, worthy of an authority. Both Pythagoreans and Peripatetics, such as the Peripatetic author of the Greek Peri Kosmou, do precisely this. Christians do something similar when they write gospels that they attribute to Jesus’s pupils, in which they accommodate their own views about Jesus. The chapter on philosophers focuses especially on polemics between competitive philosophical schools. But there are also emulation, appropriation and intertextuality. Apuleius’ De mundo is a recasting of the Peripatetic Peri Kosmou; Plutarch emulates Aristotle when he composes a work with the title Topics (Lamprias catalogue nr. 56), while he attributes the doctrine of Categories to Plato (De animae procreatione 1023B); and Galen draws on Plato in his philosophical treatises. The short chapter on philosophers therefore hardly does justice to the work of contemporary philosophers with philosophical texts and to their construction of authoritative ones.

The third chapter focuses on the Jews and considers three main communities within them, the Therapeutae, a group of contemplative philosophers, the Essenes, who are presumably connected to the Qumran texts, and those members of a rabbinic movement associated with the Mishnah. The chapter offers a good overview of how Jewish communities operated with texts. Yet the comparison with the textual strategies of the philosophers is disappointing. Both are found to be guided by authoritative texts and use allegorical interpretation as an exegetical method. The question that is not addressed here is why they turn to allegorical interpretation and how they apply it. The other issue that arises in this chapter is the orality of some ‘texts’, such as the Mishnah, which K. calls ‘pluriform’ (p. 51), because there was not one text of the Mishnah but several editions of it until it was cast in a written form in the Middle Ages. Then one wonders whether it is the religion, that is certain religious views and traditions, that are of priority to a text and eventually shape a text, in which case the religious tradition is the decisive factor shaping the identity of a community.

The fourth and longest chapter concerns the Christians. K. distinguishes three reading communities within this group (p. 71), the emergent Catholic Church represented by Irenaeus of Lyon, the emergent Catholic Church in advanced form or more philosophical Christians, represented by Clement of Alexandria, and the Valentinians, the partisans of the bishop Valentinus (c. 100–175 ce). The distinction is schematic, since one could also identify other possible communities, such as the Marcionites, as K. admits. The problem is the value of speaking of distinct textual communities, since all these Christian groups read the same texts, even though they interpret them differently. What distinguishes them is not the specific focus on certain texts, the Christian Scripture, but rather their views on certain issues that are then read into the texts. When Irenaeus claims that the Valentinians disregard the plain sense of the words (5.13.5, p. 83), this suggests that Valentinians are driven by certain views and not by the texts they read; rather, they read their fixed views into the texts.

One wonders at the end whether we can speak of textual communities in the way in which K. does. For first he assumes that such communities are distinct because of their textual authorities. But this is not true; for philosophers, Jews and Christians have a much wider network of texts than that of their own authorities, such as the Torah for the Jews, the Christian Scriptures for the Christians and Plato’s works for the Platonists. Philo, for instance, is famous for his debt to the Timaeus in his exegesis of Genesis; Christians from Justin Martyr onwards follow Philo on that; similarly, philosophers such as Numenius and Plotinus are students of Christian texts. The reason for this familiarity is that all of them, Jews, Christians and Platonist philosophers, have common issues to tackle, such as how God created the world, whether matter is a principle of creation, how the soul relates to the body, and so on. This is why they turn to texts, in order to find answers, or at least a way in which to address such issues. This is why Philo turned to the Timaeus, in order to explain Genesis in a way that makes God the sole principle of creation. Similarly, Tertullian turned to Stoic and medical texts in order to explain how the soul relates to the body, given that Christian Scripture is not illuminating on that. And Clement of Alexandria turned to Galen in order to learn about demonstration. In all these cases members of certain communities turned to texts outside those of their presumed authoritative ones. Indeed, some Christians lean so much to philosophical texts that they would qualify as philosophers, as K. admits (p. 69). If this is the case, it is not so much the community’s authoritative texts that shape the identity of an individual or of a community, not even the strategy of interpreting them, but rather the way of addressing certain burning issues, which involves not only a reading of ‘their’ texts but also the appreciation of other texts, which inspire them, that is, show them ways to address crucial issues emerging in ‘their’ communal texts.

The book does justice to the fact that this is an era in which texts play a major role for the crystallisation of views among various groups of thinkers, and it provides good insights about the text circulation among them. Yet, ultimately, it does not fully engage with the complexity in which Jews, Christians and philosophers of that time deal with the available texts in order to do justice to their assumed authorities.