This publication starts the series of the Prologue (Lives of the Saints arranged in calendar order, 12th - the first third of 15th centuries). The Prologue represents a great monument of medieval Slavic-Russian literature and includes a translated collection of brief hagiographical Slavic texts - Synaxarion. This publication is based on the oldest East Slavic copies: Sofiiskii, Lobovskii and Pskovskii - which have never been published in full. A Slavic text is accompanied by a parallel Greek text and linguistic and textual comments. Illustrations. (1.375 kg.). Also available on the subject: Orlova, T.I. Prolog XIII-XIV vv. (2000); Loseva, O.V. Zhitiia Russkikh Sviatykh v Sostave Drevnerusskikh Prologov XII - Pervoi Treti XV Vekov (2009). 2 volumes. LXXXIX, 823+856 pages. Hardcover. 16 x 24 cm. Printing 800.