During the last century there have been many discoveries that have reshaped our understanding of early monastic texts and their authorship. The writer of these two substantial volumes proposes new ones. In The real Cassian revisited he argues that the Latin monastic works traditionally ascribed to an early fifth-century monk named John Cassian, later resident in Gaul, are actually a medieval ‘augmented interpolated product originating in a far shorter Greek original by Cassian the Sabaite’, whom he identifies as an early sixth-century monk of Mar Saba in Palestine (The real Cassian revisited, 152; cf. A newly discovered Greek Father, p. xii). This Greek text, edited with substantial commentary in A newly discovered Greek Father, has historically been considered a condensed translation of selections from the Latin works. In reversing this view, Tzamalikos announces the ‘rediscovery’ of a forgotten Greek genius.

Tzamalikos was inspired by a ninth/tenth century manuscript now at the monastery of the Meteora (ms 573) that opens with the rubric ‘Book of Monk Kassianos’ followed by writings attributed to ‘Roman Monk Kassianos’ (the monastic texts edited in A newly discovered Greek Father). The manuscript concludes with the text of the Book of Revelation and a series of scholia on it, which Harnack ascribed to Origen. On the last folio of the scholia (and also of the manuscript), a note in a later hand has added, ‘Of/by Kassianos the Roman Monk’, reprising the opening title. This note led Tzamalikos to wonder if, and then to conclude that, the note indicated an inclusio, and that the scholia, too, were the work of Kassianos.

On the face of it, this is a curious deduction given that more than ninety folios of works by at least five other authors occur between the opening texts and the biblical book with its scholia. And, of course, the note on the final folio is not original. (The absence of a full description of the manuscript is frustrating, and one must go to Tzamalikos's recent edition of the scholia, or to other sources, to find it, and to discover further mysteries such as the fact that there are missing folios, including one now in St Petersburg.) Tzamalikos ‘believes’ that the manuscript was copied at Mar Saba from a now-lost sixth-century original belonging to Kassianos himself, though it is unclear why Kassianos would sandwich those ninety-plus folios of writings by others between works supposedly his own.

Tzamalikos identifies this ‘rediscovered’ theologian with the ‘Kasianos’ (one sigma) mentioned a few times by Cyril of Scythopolis. According to Cyril, Kasianos was a native of his own city, hegumen at Souka and then at Sabas's own ‘Great Laura’ in the 540s, and honoured by burial next to Sabas. The only other reference to Kasianos occurs in a list of subscribers to a synod at Constantinople in 536, where he is listed as ‘presbyter and monk of the Laura of Sabas'. From those few indications – none of which suggest that Kasianos was an author – and by inference from other writings that Tzamalikos has now attributed to him, Tzamalikos has constructed a complete biography and intellectual history. ‘Cassian the Sabaite’ was Antiochene in his theology, and inclined toward an Aristotelian rather than Neo-Platonist reading of Origen. He was devoted to the works of Gregory of Nyssa, found Theodoret to be a kindred soul, and probably knew Ps.-Dionysius personally. He had spent considerable periods of time at the Monastery of the Akoimetoi in Constantinople. He is the true author of several mis-attributed theological works and likely of others as well. (Much of this deduction can be found in the fascinating literary and philological notes accompanying the edition in A newly discovered Greek Father.) Why did this genius vanish without a trace, his works reassigned to others or left anonymous? Tzamalikos suggests that his legacy may have been destroyed in the Origenist controversies shortly after his death, and/or that he was accused of Nestorian sympathies for his partiality to Antiochene theologians (The real Cassian revisited, 259ff). By the time of Photius, who read and admired the Greek monastic works and referred to their author as ‘Kassianos of Roman birth’, the identity of the true author, Cassian the Sabaite, had been lost.

Tzamalikos works equally hard to demolish the traditional claim that there was a monk named John Cassian, likely from Scythia Minor, who wrote in Latin in Marseilles in the early fifth century (thus a full century before Cassian the Sabaite). Any ambiguities about the Latin figure – and there are indeed several, and it is good to have them chronicled – are resolved considerably less generously than the many lacunae in the vita of Cassian the Sabaite. Thus Tzamalikos maintains that Prosper of Aquitaine was not responding to Cassian's Conference 13 in his Contra collatorem; Palladius did not mean this Cassian and Germanus in his Dialogue; Gennadius' entry on Cassian was interpolated. He suggests that the sobriquet ‘Cassian the Roman’ in Meteora 573, which misled Photius, was introduced by monks of Mar Saba to protect the identity of their Kassianos, a true Greek and thus a ‘Roman’, unlike the barbaric ‘Cassian the Scythian’, who was already usurping the claim to authorship.

The strongest obstacles to Tzamalikos's thesis about the authorship of the monastic writings come from literary history and textual comparison between the Greek and Latin versions. The chronology developed for Cassian the Sabaite places him in the early sixth century, and hegumen at Mar Saba from the 540s. If the Institutes and Conferences of the Latin Cassian are indeed a later translation and expansion of the much briefer work of Cassian the Sabaite, it becomes difficult to explain the obvious influence of those Latin texts on the Regula magistri, usually dated to the 520s, and the corresponding parallels and additional influences on the Regula Benedicti, usually dated to c. 540. Tzamalikos suggests that the author of the Regula magistri translated at least some of Cassian the Sabaite and introduced it into his rule (The real Cassian revisited, 219). It is clear, however, that the Regula magistri depends on Latin Cassian rather than on a supposed translation of Greek Kassianos. To choose just one example, Latin Cassian's Institutes 4.39 inspired the Regula magistri's ladder of humility, soon adopted by the Regula Benedicti (Regula magistri 10/Regula Benedicti 7). A comparison of Latin Cassian, Greek Kassianos and Regula magistri shows the latter often following Latin Cassian word for word, even in phrases not found in Greek Kassianos. In the ultimate stage of humility, both Regula magistri and the Greek text sharpen Latin Cassian's allusion to 1 John iv.18 but in very different ways. If one is inclined to think that the dating of the Regula magistri and the Regula Benedicti is unsure, and that there might have been more time available for the creation of a bloated Latin version based on the Greek, there are still Cassiodorus' references to the Latin writings. Tzamalikos cites three of the five in a footnote (The real Cassian revisited, 98 n. 205), but does not account for their quite specific mention of important parts of the Latin works that have no Greek counterpart (for example, Conference 5 on the eight vices; Conference 9–10 on prayer; mention of Prosper's refutation of Cassian on free will, alluding to Conference 13). Most of these references date from the 540s, when ‘Cassian the Sabaite’ was still hegumen in Palestine. For Tzamalikos's argument to stand, by that time the Greek texts had already been composed and been in circulation, the Latin translation and expansion had been finished, the identity of the (living) Greek author had been suppressed, the originality of the putative Latin author was firmly established, and Cassiodorus, with his interest in both Greek and Latin literature, was taken in.

Then there are the texts themselves. The Latin corpus of Cassian is vastly larger than the Greek Kassianos, at least fifteen times so. (Tzamalikos does not claim that the Greek work was ever longer than what is presented in A newly discovered Greek Father.) There is no part of Greek Kassianos not found in Latin Cassian. Additions (as Tzamalikos would have it) or omissions (the usual view) are evident within sentences, as well as within paragraphs and at the level of whole chapters, not to mention the many entire books that are not found in the Greek. The Latin works have a careful plan and execution. If they are a translation and expansion of the Greek Kassianos, this is literary remodelling and inflation on a massive scale. It had to be the work of someone who knew Greek well enough not only to translate, but also, in the sections original to him, to base his Latin citations of Psalms, Proverbs and other books beloved of monks on the LXX, betokening a direct experience of monastic life in a Greek-speaking environment. The Latin work's exegesis of the story of Martha and Mary (Conference 1.8) turns on a variant reading known in the Greek but not in the Latin tradition; Greek Kassianos has parts of this conference, but not this part. Latin Cassian also had direct knowledge of the writings of Evagrius, as is evident in the way that he structured his own works (for example, the opening book of the Institutes is an allegorical interpretation of the monastic habit, just like Evagrius' Letter to Anatolios, the preface to his foundational Praktikos). Evagrius' influence is pervasive in the content of both Institutes and Conferences, and the same can be said about Origen. Much of this is missing in Greek Kassianos, for example the explanation of the three origins of thoughts (Conference 1.19), an analysis clearly derived from Origen and Evagrius. Nor does Greek Kassianos feature the comparison of the discernment of thoughts to the work of an experienced money-changer (Conference 1.20; cf. 2.9); Cassian is an early Latin witness to this Greek apocryphon. The Cassian of the De incarnatione may have been a ‘mediocre’ theologian (The real Cassian revisited, 129), but the author of these extensive Latin monastic texts knew his subject, and its main sources, very well indeed.

Tzamalikos seems unwilling even to entertain the possibility that the Latin texts were written first, seizing upon – and exaggerating – Owen Chadwick's observations about apparent disturbances in the textual tradition as proof that the Latin corpus is rotten (The real Cassian revisited, 100, 140, etc.). But as one compares the Greek and the Latin closely, it is difficult to avoid the sense that the Greek work is in fact an edited version of the Latin, and that its creator was intent on editing out Evagrian themes such as the recurring emphases on abiding purity, contemplation, ‘seeing God’, enduring perfection. He altogether avoided topics such as imageless prayer (as in Conference 10) and, as noted above, biblical texts of unreliable provenance. If Latin Cassian knew the Greek ascetic tradition so well that he could craft such a massive work, pervaded by the thought of Origen and Evagrius, and sprinkled with references to monastic Egypt, it seems strange that he would have bothered to use the much skimpier Greek Kassianos as a starting point. The knife is easier to wield than the pen: why spend so much time inserting words within sentences and sentences within paragraphs? On the other hand, an elegant Greek epitome of a much longer Latin work, crafted by someone with a strong sense of the language (as demonstrated in Tzamalikos's commentary) and certain theological biases seems more plausible. This person might, indeed, have been the author of the scholia and even other works, though such an investigation lies outside the scope of this review.

Tzamalikos asserts that he is objective and motivated purely by science. And yet the work is marred by dismissive remarks that are surprising in a modern scholarly publication. He repeatedly scorns the possibility that any non-Greek would have been capable of such profound monastic thought, or so familiar with Greek literature and terminology. Here is one example among many: ‘could any Latin author have composed such a Latin text in the first place, of which Codex 573 could only have been a mere translation[?]’ (The real Cassian revisited, 101). He claims, for example, that it would have been impossible for a Latin to employ Aristotle's distinction between skopos and telos (as in Conference 1; The real Cassian revisited, 65, cf. 101). Really? Even a Latin who knew his Origen and Evagrius? Who could have read Aristotle directly or at least gleaned this from one of the myriad popular manuals of the day? We are growing in our understanding of the rich – and mutual – interaction between Latins and Greeks in the fifth and sixth centuries. It is in those milieux, in which Latin texts could be and were translated into Greek, that we should situate the creator of the Greek Kassianos, perhaps not a Sabaite, but surely a monk.