Our venerable father '''Isaac the Confessor''' (also known as '''Isaac of Dalmatia''') is commemorated by the Orthodox Church on [[March 22]], [[May 30]], and [[August 3]]. He is known for his struggle against the [[Arianism|Arian]] [[heresy]] during the reigns of the Arian emperor Valens and the Orthodox emperor [[Theodosius the Great (Emperoremperor)|Theodosius]].