Every year on June 12, the Orthodox Church honors the memory of Saint Isaakis the confessor, hegumen of Dalmatia, who lived in the 4th century in Syria and led a secluded, ascetic lifestyle. The saint founded a monastery near Constantinople.

In 378, Saint Isaac predicted that Emperor Valens must open churches to Orthodox people or face his death by fire. The emperor disobeyed the saint, so the prophecy came true. After this incident, Isaiah began to be revered as a great prophet. The monk became the first abbot of Dalmatia. Isaac died on May 30, 383.