The Syriac version of the Apocalypse is divided into two subversions, the Philoxenian and the Harklean. Of the latter version, some ten manuscripts are extant. A new critical edition based on these manuscripts provides many insights in the form of the Greek text of the Apocalypse current in Late Antiquity and the Early Middle Ages, not only through the text itself, but also via their variant readings and their marginal notes.