The paper will offer a short codicological and palaeographical description of the unpublished XIV century manuscript Evr. IIA 1980 from the National Library of Russia (St. Petersburg). The manuscript in question contains a glossary on the Prophets, mainly Isaiah. The material provided by the glossary is of no little exegetical interest and offers a good occasion for extensive comparison of lexical material between the ancient Jewish translations, including the Three, up to the most recent Judeo-Greek versions of Isaiah. Covert references to recent political events are also found.