thumb|An [[Eastern Orthodox Church|Eastern Orthodox cross]]
April 4 – Eastern Orthodox liturgical calendar – April 6
All fixed commemorations below are observed on April 18 by Eastern Orthodox Churches on the Old Calendar.
For April 4th, Orthodox Churches on the Old Calendar commemorate the Saints listed on March 23.
Saints
- Martyrs Claudius, Diodorus, Victor, Victorinus, Pappias, Serapion and Nicephorus, at Corinth (251 or 258)
- Martyrs Theodulus, Reader, and Agathopodes, Deacon, and those with them, at Thessaloniki (c. 303) <small>(see also: April 4 - Greek)</small>
- Martyrs Zenon, by fire, Maximus, Terentius and Pompeius, by the sword (250) <small>(see also: October 28, March 13, April 10)</small>
- Martyr Thermos (Fermus, Firmus), by fire.
- The Holy Noble Lady (sister of martyr Thermos/Fermus), and her Servant, martyrs, by the sword.
- Holy Five Young Virgin-Martyrs of Lesbos, by the sword.
- Virgin-martyr Theodora and Martyr Didymus the Soldier, of Alexandria (304) <small>(see also: May 27)</small>
- Venerable Martyr Ypomoni (Hypomoni, Evpomoni).
- Venerable Publius of Egypt, monk (4th century) <small>(see also: April 4 - Greek)</small>
- Saints Theonas, Symeon, and Phorbinus, of Egypt (4th century)
- Venerable Plato the Confessor, Abbot of the Studion (813) <small>(see also: April 4 - Greek)</small>
- Venerable Theodora of Thessaloniki (886)
Pre-Schism Western saints
- Holy Martyrs of North-West Africa, a large group martyred at the Easter liturgy by Genseric, the Arian King of the Vandals (459)