Cambridge, St John's College 42 (B. 20) is a Latin manuscript, dated as twelfth century and tentatively placed at Worcester. It contains 136 folios, closely written in double columns of forty-five lines each, in which a range of abbreviations has been used. By these means a quantity of material has been presented, including two collections of homilies/sermons, a calendar, extracts from the works of named authors and miscellaneous smaller items. The most notable of the sermons for Anglo-Saxonists is a new text of Archbishop Wulfstan's Latin composition, De Anticristo, but it keeps company with other anonymous sermons, some of which are variant texts of sermons copied or composed in English manuscripts of the Anglo-Saxon historical period. The manuscript needs a closer study than those done by M.R. James, who catalogued the anonymous items without identification, or by H. Schenkl, whose catalogue is incomplete although it includes some identifications. Identification of the anonymous items, with notice of parallel texts in other manuscripts where possible, helps to confirm the date of the manuscript, suggests that its place of origin was Worcester, and allows speculation on the canon of Wulfstan's Latin writing.