Achillius of Larissa

Saint Achillius of Larissa was born in Greece, though the details of his early life are not known. He rose to serve the Church as metropolitan bishop of Larissa in Thessaly during the fourth century, a time when the faith was fiercely tested by division and error. Achillius is especially remembered for his steadfast witness to the true divinity of Christ at the First Council of Nicaea, where he defended orthodox teaching against Arianism. Tradition recounts that, to confound those who denied the Son’s equality with the Father, he called upon God and oil miraculously flowed from a stone—an outward sign pointing to the truth he proclaimed. Returning to his people, he labored zealously to strengthen Christian life, overturning pagan practices, building up churches, and delivering many from demonic oppression. Achillius died in Larissa around the year 330, and his relics were later translated to Prespa, where devotion to him endured for centuries. He is venerated as patron of Larissa and Grevena. His feast day is May 15.