The Life of Dositheos (Vita Dosithei, BHG 2117) presents readers with an unusual Greek word:   “τὰς κλύστας.”  Hitherto this word has been misunderstood as referring to bread soaked in wine.  That reading, and the Byzantine lexicographical tradition behind it, will be shown to be untenable.  Instead, it will be demonstrated that the knife (μαχαίριον) in question is a scalpel.   It either cuts “κλυστήρας” or “κύστας.”  In the first case, the scalpel is intended for the preparation of enema equipment; in the second case, the performance of lithotomies.  In either case, the objects to be cut are bladders.  Having established these lexical and translational points, the Life will be presented as a valuable, and so far under-appreciated, witness to the level and range of healthcare in Late antique Byzantine monasteries as well as patronage networks in Gaza.