[6] He studied, later on, the Old and New Testament writings, with the result that he abandoned his Neoplatonism for Christianity, and with his wife and his daughter, traditionally known as Saint Abra of Poitiers, was baptized and received into the Church.

[3] About the same time, Hilary wrote to Emperor Constantius II a remonstrance against the persecutions by which the Arians had sought to crush their opponents (Ad Constantium Augustum liber primus, of which the most probable date is 355).

[8] His efforts did not succeed at first, for at the synod of Biterrae (Béziers), summoned by the emperor in 356 with the professed purpose of settling the longstanding dispute, an imperial rescript banished the new bishop, along with Rhodanus of Toulouse, to Phrygia, a stronghold of Arianism.

[12] The De trinitate libri XII, composed in 359 and 360, was the first successful expression in Latin of that Council's theological subtleties originally elaborated in Greek.

When this council ratified the decisions of Ariminum and Seleucia, Hilary responded with the bitter In Constantium, which attacked the Emperor Constantius as Antichrist and persecutor of orthodox Christians.

[4] Hilary's urgent and repeated requests for public debates with his opponents, especially with Ursacius and Valens, proved at last so inconvenient that he was sent back to his diocese, which he appears to have reached about 361, within a very short time of the accession of Emperor Julian.

[11] On returning to his diocese in 361, Hilary spent most of the first two or three years trying to persuade the local clergy that the homoion confession was merely a cover for traditional Arian subordinationism.

Upon returning home, Hilary in 365, published the Contra Arianos vel Auxentium Mediolanensem liber, describing his unsuccessful efforts against Auxentius.

He also, perhaps at a somewhat earlier date, published the Contra Constantium Augustum liber, accusing the deceased emperor as having been the Antichrist, a rebel against God, "a tyrant whose sole object had been to make a gift to the devil of that world for which Christ had suffered.

[16] While Hilary closely followed the two great Alexandrians, Origen and Athanasius, in exegesis and Christology respectively, his work shows many traces of vigorous independent thought.

Hilary's commentary was strongly influenced by Tertullian and Cyprian, and made use of several classical writers, including Cicero, Quintilian, Pliny and the Roman historians.

[24] Sulpicius Severus' Vita Sancti Martini led to a cult of Saint Hilary as well as of St. Martin of Tours which spread early to western Britain.

In France most dedications to Saint Hilary are styled "Saint-Hilaire" and lie west (and north) of the Massif Central; the cult in this region eventually extended to Canada.

In southern Spain the feast of San Hilario is celebrated in the village of Comares with a Mass, a procession and local Verdiales dances.