Achillius of Larissa

Saint Achillius of Larissa (also spelled Achilles, Achilleus, or Achillas; Greek: Hagios Achilleios) was a Christian bishop of the fourth century who occupied the see of Larissa in Thessaly. Later Greek hagiographical sources state that he was a native of Cappadocia, though no contemporary document records his parentage, the date of his birth, or the circumstances of his early life. He is known to history as bishop of Larissa in the reign of Constantine the Great. Larissa was the principal city of Thessaly and an important ecclesiastical centre; its bishop ranked among the notable prelates of the Greek provinces of the Roman Empire. Almost nothing about his formation or the date of his consecration can be verified from sources independent of later synaxaria.

The most securely attested event of his career is his participation in the First Council of Nicaea in 325. Episcopal lists associated with that council include a bishop of Larissa, and church tradition identifies this figure with Achillius. At Nicaea he is remembered as a defender of the teaching that the Son is of one essence with the Father, against the doctrine associated with Arius. A famous story, preserved in later synaxaria rather than in the official acts of the council, relates that Achillius challenged Arian spokesmen by taking up a stone and declaring that if the Son is truly consubstantial with the Father, oil should flow from it; oil then poured forth. Whether historical or legendary, the episode became a standard feature of his iconography and of Orthodox preaching about the council, and it is the miracle most closely attached to his name.

Tradition further describes Achillius as an active pastor who worked to suppress remaining pagan cults in Thessaly, to found churches, and to relieve the poor, and who was credited with miraculous healings. These notices belong to the conventional repertoire of episcopal hagiography and cannot be independently confirmed, but they shaped his later cult. He died at Larissa, according to the received Orthodox chronology in the year 330, not many years after the Nicene council, and was buried in his own city. His tomb attracted veneration, and he came to be regarded as the heavenly protector of Larissa.

The later history of his relics is better documented in medieval sources. In the late tenth century, during the wars between the Byzantine Empire and the First Bulgarian Empire, Tsar Samuel captured Larissa (commonly dated to 985 or 986) and removed the relics of Achillius to a small island in Lake Prespa. The island thereafter bore the name Agios Achilleios. Samuel founded a large basilica there to house the relics; its ruins remain a significant archaeological site. The translation spread Achillius’s cult in the western Balkans. In the Eastern Orthodox Church he is commemorated on 15 May and is the patron saint of the city of Larissa. No record exists of a formal canonization by a pope or patriarch in the later juridical sense; his cult belongs to the ancient, locally rooted veneration of a Nicene father and wonderworking bishop, and he remains an obscure figure in the Latin West.