Service in the Army of Julian
John lived in the fourth century and served as a soldier under the emperor Julian the Apostate, whose reign (361-363) saw a renewed official hostility toward Christianity. John was placed among those tasked with hunting down believers, but he remained a Christian in secret and turned his office to their protection.
According to the synaxarion he freed Christians who had been arrested, warned others of dangers threatening them, and assisted them in escaping. Beyond his fellow Christians, he is remembered for wider works of mercy: visiting the sick and the imprisoned, comforting the suffering, and helping those in poverty, while maintaining a personal discipline of prayer and fasting.