August 21 (Eastern Orthodox liturgics)

August 20 - Eastern Orthodox Church calendar - August 22

All fixed commemorations below are observed on September 3 by Orthodox Churches on the Old Calendar.

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

Holy Forefathers Abraham, Isaac, and Jacob.

Apostle Thaddeus of Edessa.

Stained-glass windows at Clermont-Ferrand cathedral, with Saint Sidonius Apollinaris.

Saint Abramius of Smolensk, Wonderworker.

Saint Nectarius (Kephalas), Metropolitan of Pentapolis (North Africa).

Greek Sources

Russian Sources

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Wikipedia