29 May - Saint Maximin, born in Silly, Roman Gaul, becomes Bishop of Trier around 341/342 during the reign of the sons of Constantine the Great. He is an opponent of Arianism, and a friend of Athanasius of Alexandria, who takes refuge in his home in Trier during his exile in 336-37 and again in 343. Thanks to him, Athanasius met Caesar Constantine II before the latter became emperor.

Maximin took part in the Council of Sardius convened by Pope Julius I, and opposed the bishops of Aria. The meeting of Sardius is the site of theological and canonical discord, which testifies to the differences between the currents running through the Christian communities of the time, and to the differences in intellectual traditions between the Greek East and the Latin West, at a time when these Christian communities hardly exceed five per cent of the population of the Empire, and are still relatively concentrated in the East and in the African provinces.

Maximin worked to convince the Western Roman emperors to support the Western Catholic Church and Nicene Orthodoxy in their struggle against Arianism. He also led evangelization campaigns in his diocese and in nearby territories such as Lorraine and as far as Alsace, accompanied in particular by Paulin de Trèves, who like him was originally from Aquitaine and whom he ordained a priest.

Maximin died in Poitiers where he would have come to see his parents. His body was repatriated to Trier, and was buried in the cemetery next to the north gate of Trier, in the crypt of a church dedicated to St. John the Evangelist, and then in an abbey that later became St. Maximin's Abbey in Trier.

Maximin is depicted as a bishop, with the book, the model of a church, and, borrowing from the legend of Corbinian of Freising, a bear, which is said to have killed his beast of burden and then had to carry his luggage on a trip to Rome carrying his travelling bag. It is invoked as protection against perjury, loss at sea and destructive rains.