April 25 (Eastern Orthodox liturgics)

Apr. 24 - Eastern Orthodox Church calendar - Apr. 26

All fixed commemorations below are observed on May 8 by Orthodox Churches on the Old Calendar.

For April 25th, Orthodox Churches on the Old Calendar commemorate the Saints listed on April 12.

Holy Apostle and Evangelist Mark.

Saint Sylvester of Obnorsk.

Greek Sources

Russian Sources

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Wikipedia