In this paper I present the investigation of five Greek manuscripts of the 9th–11th century, which were collected and deposited at the monastery of St. Catherine by the person named Ṣā‛id bn Dānīl bn Bišr. These manuscripts were marked by his Arabic record, presumably dating back to the 12th century. Thus, we have a trace of the private library of the 12th century, owned by the Arabic-speaking collector of “antique” Greek manuscripts. In the paper the dating and localization of all five Greek codes were clarified. In addition, the study of the majuscule fragment NE MG 25 and the Arabic record on it allows us to make substantial amendment to the reconstruction of the ancient stage of the manuscript tradition of works of Gregory of Nazianzus: establishing the existence in the 9th century Byzantium a two-volume edition of Nazianzus’ Homilies.
