Our venerable Father '''Theodosius of the Kiev Caves''', along with [[Anthony of the Kiev Caves|St Anthony of Kiev]], is considered to be founder in the eleventh century of the Kiev Pechersk Lavra ([[Monastery of the Kiev Caves]]) and of [[monasticism]] in Russia. He brought [[cenobitic]] monasticism to Kievan Rus'. His [[feast]] day is [[May 3]].

The introduction of the Studion rule in the Kiev Cave monastery has been considered to be St. Theodosius’ greatest achievement. This rule would later spread to all Rus. He is considered today to be one of the first organizers of monasticism in the [[Church of Russia]]. St. Theodosius is also commemorated on [[August 28]] with the [[synaxis of those whose relics repose in the Far Caves of St Theodosius]].