Markus von Arethusa
Feast: 29 March (not on the universal Roman calendar; kept in the Roman Martyrology or local calendars)
Who they were
Commemoration of Saint Mark, bishop of Arethusa in Syria, who at the time of the Arian controversy never strayed from the right faith and under the emperor Julian the Apostate suffered violent harassment; he was hailed by Saint Gregory Nazianzen as an outstanding figure and an elder of most holy life.
The miracles
There was never a formal cause: he has been honoured as a saint since before the Church's formal processes began.
Why that counted as sanctity
The Roman Martyrology remembers him on 29 March as a bishop of Arethusa who held to the right faith in the Arian controversy and suffered under Julian the Apostate.
- Roman Martyrology, 29 March (Italian Bishops' Conference, Santo del giorno)
- Wikidata Q594713 — dates, feast day and identifiers (CC0)
Checked against the sources listed on 22 September 2026. Corrections welcome.