Saint Isidore was born into a noble family in Alexandria, a centre for arts and sciences of his time. He received a brilliant education and could look forward to a brilliant secular career as a teacher, philosopher or civil servant. He had already begun to teach rhetoric when he realized that the true object of his life was to serve God. He abandoned his worldly life and went to ascetise as a hermit in the Egyptian desert. He was ordained as a priest a year later, and then joined a monastery, where he lived for the rest of his life and eventually became its abbot.
In his priestly and monastic service, he put his eloquence and talent as a writer and philosopher to the service of God. He considered himself a follower of John Chrysostom, having read his writings and, possibly, met him in person. Like John Chrysostom, he concerned himself with how the teachings and doctrines of our faith translate into our daily lives and practical choices as Christians. In his view, this ‘practical wisdom’ was “the foundation of the edifice and the edifice itself”, logic was its "embellishment", and contemplation of its "crown". He wrote thousands of epistles. His surviving writings contain deep theological reflections and moral interpretations of the Holy Scripture.
To his contemporaries and followers, he was more than an outstanding religious thinker. They viewed him as a model of piety and monastic life, a man who practised the wisdom of his teachings and showed others the way to the Truth by his example. Evagrius, a sixth-century wrote of Saint Isidore, “his life seemed to everyone the life of an angel upon the earth.” Nikēphóros Callistus, of the ninth century, praised him as “a vital and inspired pillar of monastic rules and divine vision.
At the monastery where he was ascetising, he earned himself respect for his spiritual wisdom, asceticism, knowledgeability, and deep understanding of the human soul. In acknowledgement of these talents, they chose them as their Hegumen. He supported Saint John Chrysostom when he was persecuted at the behest of the empress Eudoxia and Archbishop Theophilus. The successor to Theophilus, Cyril treated St. Isidore as his spiritual father. Saint Isidore convinced Cyril to support the veneration of John Chrysostom.
He was one among the people behind the calling of the Third Ecumenical Council of Ephesus (451), where the heresy of Nestorius of condemned. Yet he used his influence on Cyril to call mercy on the individuals caught up in the heresy, whom Cyril was inclined to treat harshly. “I adjure you to put an end to this dissension lest a permanent breach be made under the pretext of piety,” wrote St. Isidore. When his growing influence provoked his persecution from the secular and church authorities of Byzantine, he received it dispassionately, departing to the Lord around 440.
