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May 18 - Eastern Orthodox Church calendar - May 20
All fixed commemorations below celebrated on June 1 by Orthodox Churches on the Old Calendar.
For May 19th, Orthodox Churches on the Old Calendar commemorate the Saints listed on May 6.
Saints
- Hieromartyrs Patricius (Patrick), Bishop of Prusa, and his companions: the Presbyters Acacius, Menander, and Polyenos (c. 100 or c. 362)
- Martyrs Parthenius and his brother Calogerius, at Rome (250)
- Martyr Philoterus of Nicomedia (303)
- Martyr Acoluthus of Hermopolis, Egypt (303)
- Martyr Cyriaca (Kyriake) and the six holy virgin-martyrs in Nicomedia (307)
- Martyr Theotima of Nicomedia (311)
- Saint John, Bishop of Gothia in the Crimea (787)
Pre-Schism Western saints
- Martyr Pudens, the senator (c. 160)
- Virgin-Martyr Pudentiana (Potentiana), daughter of Saint Pudens the senator (160)
- Saint Cyril of Trier, Bishop of Trier, (5th century)
- Saint Adolphus (Hadulf), ascetic of the Benedictine Abbey of St. Vaast, in Arras, and later Bishop of Arras Cambrai in the north of France (728)
- Saint Dunstan, Archbishop of Canterbury (988)
Post-Schism Orthodox saints
- Right-believing Prince Vladimir II (Basil) Monomakh of Kievan Rus (1125)
:* Barnabas, Gennadius, Gerasimus, Germanus (Herman), Theognostus, Theoctistus, Jeremiah, John, Joseph, Conon, Cyril, Maximus and Mark.
- Right-Believing Great Prince Dmitry Donskoy, Great Prince of Moscow (1389) <small>(see also: May 9th)</small>
- Venerable Eudoxia of Moscow (in monasticism Euphrosyne), Grand-Duchess of Moscow (1407)
- Venerable Sinaites of Serbia (from Ravanica) (14th century): <small>(see also: May 6)</small>
:* Romulus, Romanus, Nestor, Sisoes, Zosimas, Gregory, Nicodemus, and Cyril, the Sinaites - disciples of Gregory of Sinai (Mount Athos).
- Saint Cornelius of Paleostrov, founder of Paleostrov Monastery, Karelia (1420) and his disciple Abramius (15th century)
- Venerable Cornelius of Komel (Vologda), Abbot and Wonderworker (1537)
- Saint Sergius of Shukhtov (Shukhtom), monk (1609)
- Saint Nicholas Rynin of Vologda, Fool-for-Christ (1837)
:* Hieromartyr Matthew Voznesensky (1919)
:* Hieromartyr Victor Karakulin (1937)
:* Hieromartyr Onuphrius (Gagaliuk), Archbishop of Kursk and Oboyansk (1938) <small>(see also June 1)</small>
:* New Hieromartyrs Anthony (Pankeyev), Bishop of Belgorod (1938), and with him: Alexander Yeroshov, Michael Deineka, Hippolytus Krasnovsky, Nicholas Kulakov, Basil Ivanov, Nicholas Sadovsky, Maximus Bogdanov, Alexander Saulsky, Paul Bryantsev, Paul Popov, and Gregory (Bogoyavlensky).
::* Martyr: Michael (Voznesensky)
- New Hieromartyr Valentine Lukyanov, Hieromonk, of Romashkovo, Moscow (1940)
- Synaxis of the Hieromartyrs of Kharkov:
