May 31 (Eastern Orthodox liturgics)
May 30 - Eastern Orthodox Church calendar - June 1
All fixed commemorations below celebrated on June 13 by Orthodox Churches on the Old Calendar.
For May 31, Orthodox Churches on the Old Calendar commemorate the Saints listed on May 18.
Saints
- Apostle Hermes of Philippopolis, of the Seventy Apostles
- Martyr Hermias of Comana
- Martyr Magus, who converted upon witnessing the martyrdom of Hermias
- Martyr Philosophus at Alexandria
- Martyrs Eusebios and Charalampos, in Nicomedia, by fire.
- Five Martyrs of Ashkelon, dragged to death.
- Saint Eustathius, Patriarch of Constantinople
Pre-Schism Western saints
- Virgin-martyr Petronilla, at Rome
- Martyr Crescentian, in Sassari in Sardinia
- Martyrs Cantius, Cantian, Cantianilla and Protus, in Aquileia
- Saint Sylvius of Toulouse, Bishop of Lyon
- Saint Lupicinus of Verona, Bishop of Verona, described as 'the most holy, the best of bishops'
- Saint Paschasius, Deacon and Confessor in Rome, who is mentioned by Pope Gregory I
- Saint Winnow, Mancus and Myrbad, Irish saints who lived in Cornwall where churches are dedicated to them
Post-Schism Orthodox saints
- Saint Philotheus of Tobolsk, Metropolitan of Tobolsk and the "Apostle of Siberia"
New martyrs and confessors
- Hieromartyr Archpriest Philosophus, with his sons Boris and Nicholas, in St. Petersburg
- Hieromartyrs Hierotheus, Bishop of Nikolsk, and Hieroschemamonk Seraphim
Other commemorations
- First translation of the relics of Hieromartyr Philip II, Metropolitan of Moscow and all Russia, to Solovki.
- Repose of Archimandrite Macarius of Peshnosha Monastery, disciple of Blessed Theodore of Sanaxar
- Finding of the relics of New Martyr Nicholas the Deacon, of Mytilene