December 21 (Eastern Orthodox liturgics)

Dec. 20 - Eastern Orthodox Church calendar - Dec. 22

All fixed commemorations below celebrated on January 3 by Orthodox Churches on the Old Calendar.

For December 21st, Orthodox Churches on the Old Calendar commemorate the Saints listed on December 8.

St. Juliana of Nicomedia.

St. Peter of Kiev, Metropolitan of Kiev and Moscow, Wonderworker of All Russia.

Icon of St. Tryphon of Vyatka and Procopius Vyatka (17th century, Vyatka (Kirov) Museum)

Greek Sources

Russian Sources

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Wikipedia