Constans dispatched him after the Council of Sardica, along with two bishops, Vincentius of Capua and Euphrates of Cologne, to the court of his brother, Constantius II at Antioch, with a letter from Constans demanding that Constantius restore the Patriarch of Alexandria Athanasius to his see.
His first recorded act was, after a synod had been held at Rome, to write to Emperor Constantius II, then in quarters at Arles (353–354), asking that a council might be called at Aquileia with reference to the affairs of Athanasius of Alexandria, but his messenger Vincentius of Capua was compelled by the emperor at a conciliabulum held in Arles to subscribe against his will to a condemnation of the orthodox patriarch of Alexandria.
The former diocese of Digne was evangelized by Saints Domninus and Vincentius who came from North Africa in the second half of the fourth century with Saint Marcellinus, the Apostle of Embrun.