I will summarize only the general idea of my communication.
Honigmann’s thesis that the core of the CD was written by Peter Iberian was rejected by the most of scholars already in the 1950s, but was rescued from oblivion by Michel van Esbroeck.
Honigmann pointed out two facts.
1. John the Eunuch, the cell-mate of Peter Iberian, saw about 444 a vision of the heavenly hierarchies that could be the pattern of the structure of hierarchies described in the CD,
2. John the Eunuch died on October 4, the memory day of Hierotheos of Athens; October 3 is the memory day of Dionysius Areopagite. Given that the relations between Hierotheos and Dionysios as described in the CD were close to the relations between John and Peter Iberian, it is probable that the memories of 3 and 4 October pertain to Peter and John, while pseudonymised as they are in the CD.
There were several arguments which were put forward against this thesis. Michel van Esbrock answered to all of them showing that they do not have decisive value.
Among the arguments given by van Esbroeck, I would especially express three.
1. Irénée Hausherr said against Honigmann that Peter Iberian was, at the end of his life, a disciple of Isaiah of Gaza, a severe ascetic with no secular philosophical interest. It is unlikely, therefore, that Peter wrote the Corpus. To this, van Esbroeck answered by pointing out that Peter ascetical milieu in Palestine was not only Isaiah. His first milieu was that of Empress Eudocia, his de facto stepmother. However, she was a daughter of an Athenian philosopher and was Platonic philosopher and poet herself. Moreover, she explained in wording of Platonic philosophy and Greek poetry the Christian truths. Therefore, the argument of Hausherr does not hold. I elaborate on this van Esbroeck’s argument further, exploring in more details the ascetic milieu of Eudocia and Peter Iberian. Both belonged to disciples of Melania the Younger (died in 439), a granddaughter of Melania the Elder who was, in turn, the spiritual mentor of Evagrius Ponticus. There are several other details allowing to say that Peter Iberian would be able and interested in writing in strong Platonic terms.
2. Van Esbroeck’s most important argument is based on the Dormition feast. Dormition of the Theotokos as a new festivity was established in Palestine roughly in the epoch of Peter Iberian. The corresponding hagiographical legends were so-called Transitus of Theotokos. These Transitus describe the vision of opened heaven when apostles saw the angelic hierarchies and Christ descending through them to take the soul of Theotokos (a parallel to the Incarnation/Announciation). However, such is the contents of the whole Corpus (its main topics is, indeed, not Theotokos herself but the hierarchies and descending of Christ) and the vision of John the Eunuch.
3. The third main argument of van Esbroeck was dealing with elaboration of the accessible to us recension of the Corpus based on the Urtext of Peter Iberian. This recension became pseudonymised due to the efforts of some disciples of Peter after his death, in about 500, in the circumstances of polemics against some kind of unorthodox Origenism like that of the so-called Book of Hierotheos. During this reworking, the links between the Corpus and the Dormition were additionally expressed. The text of the On Divine Names acquired the passage describing the Dormition.
My own elaboration on these van Esbroeck’s arguments could be summarized as following (omitting all my polemical digressions).
1. In the Corpus itself there is a clear sign that it was produced in the milieu of Eudocia. This could by demonstrated by an approach that I call “philological.” More than 30 year ago, a brilliant Russian philologist Sergei Averintsev pointed out that there is quite specific stylistic correspondence between the Corpus and two poems of Nonnus of Panopolis, one of these poems being pagan and dedicated to the god Dionysus and another one being Christian paraphrase of the Gospel of John. However, the author of the Christian poem borrowed verbatim from the pagan one. Both Nonnus and the author of the Corpus are describing their object not by indication of what it is, but by indication of what it is not. Thus, their long enumeration that something is not that, not that, not that, and so on.
I have added to this Averintsev’s observation the known fact that Nonnus has severely impacted one of the leading persons of the milieu of Eudocia, Cyrus of Panopolis—a poet (probably, the most important poet of the whole this epoch), prefect of Constantinople who was helping Eudocia to reshape the cult of the Virgin, then bishop and theologian and the disciple of Daniel the Stylite. It is also important that the Gospel paraphrase as well as Cyrus and Eudocia were inspired by the Christology of Cyril of Alexandria, as well as Peter Iberian. After the promulgation of the Henotikon of Zeno Daniel the Stylite was one of the principal spiritual authorities approving this act and Peter Iberian was loyal to the Henotikon. However, Henotikon resolved, in Peter’s lifetime, the problems related to the Council of Chalcedon in the East. This Council was not a pretext for Church division until the time of “monophysite revolution” after 505.
2. The famous expression θεανδρικὴ ἐνέργεια is but a hallmark of the milieu of Eudocia. The wording of “god male” instead of “god man” is going back to the Greek poetry, up to Pindarus. However, such terminology as applied to Christ is known, before Dionysius, from the one source only, the Gospel paraphrase of Nonnus. This paraphrase does never use the term “God man”, but, instead, uses two times the term “God male” applied to Christ.
3. The feast of Dormition was even more important for Eudocia’s milieu than van Esbroeck thought. I omit here many important details, but my conclusion is the following: the feast of Dormition was established in Palestine after 438 and, most probably, after 443 and certainly before 449, therefore, about the date when John the Eunuch saw his vision of hierarchies, about 444. It is very likely that this vision was pertaining to the first celebration of the Dormition feast in Gethsemane.
4. Moreover, I have added some data to the history of the liturgical memories of Hierotheos and Dionysius. Already van Esbreock pointed out that, in the Coptic tradition, the memory of Hierotheos on April, 16 is inscribed in the Coptic Dormition cycle: it is exactly the middle between the Coptic date of Dormition and deposition (January 16) and the Assumption (August 9). I could add that the dates of the Byzantine (Chalcedonite as well as anti-Chalcedonite Syrian) tradition, October 3 and 4, are connected to the Byzantine date of Dormition on August 15 (actual, to my evaluation, since about 500, the date of appearance of the pseudonymised Corpus): October 3 is the fiftieth day after August 15, a kind of the Pentecost, given that Dormition is a kind of Easter (indeed, we have some documents attesting the existence of a tradition to call the Dormition “Easter”).
5. So, my most important conclusion is that we have to look for the author of the Corpus in the milieu connected to Empress Eudocia.
6. It is always probable that such an author is an otherwise unknown person. However, in our case we have to look not for a single man but for a pair of visionary teacher and his disciple, like Hierotheos and Dionysius. Therefore, the number of possibilities is severely restricted. It is not so likely that the figure of a visionary teacher could pass unnoticed.
7. In the pertinent milieu, we have several reputed visionary teachers, e.g., apart from John the Eunuch, Peter Iberian himself, Daniel the Stylite, and, probably, even Melania the Younger (who died before the Dormition feast was established, and so, could be excluded, anyway). However, in their hagiographical dossiers we have nothing similar to the vision of hierarchies as in the vision of John the Eunuch. Therefore, I think the most natural solution to accept that it was, ideed, John the Eunuch who has had a spiritual experience described in the Platonic terms by the author of the Urtext of the Corpus, who, in this case, could be only Peter Iberian
I have to acknowledge that my argument will be unconvincing to those who take as granted that the author of the Corpus was originally a neoplatonic philosopher and direct disciple of the pagan teachers. I would say about this attitude that there are several reasons not to accept it, one of these reasons being methodological: the Corpus could be read (and historically, indeed, was read) in a dozen of internally non-contradicting manners, and so, its philosophical and theological reading will be never able to lead to define what of these readings is that of the author. This is why, I think, we have to start from the definition of the Sitz im Leben by other means, including those of philology and critical hagiography.