“They didn’t know who they are.” This is how Hilary summed up the problem with the Arian heretics of the fourth century. Hilary, on the other hand, knew very well who he was, a child of a loving God who had inherited eternal life through belief in the Son of God. He hadn’t been raised as a Christian but he had felt a wonder at the gift of life and a desire to find out the meaning of that gift.
Hilary tells us, he “chanced upon” the Hebrew and Christian Scriptures. When he read the verse where God tells Moses “I AM WHO I AM” (Exodus 3:14), Hilary said, “I was frankly amazed at such a clear definition of God, which expressed the incomprehensible knowledge of the divine nature in words most suited to human intelligence.” In the Psalms and the Prophets he found descriptions of God’s power, concern, and beauty. For example in Psalm 139, “Where shall I go from your spirit?”, he found confirmation that God was everywhere and omnipotent.
After becoming a Christian, he was elected bishop of Poitiers in what is now France by the laity and clergy. He was already married with one daughter named Apra.
Not everyone at that time had the same idea of who they were. The Arians did not believe in the divinity of Christ and the Arians had a lot of power including the support of the emperor Constantius. This resulted in many persecutions. When Hilary refused to support their condemnation of Saint Athanasius he was exiled from Poitiers to the East in 356. The Arians couldn’t have had a worse plan — for themselves.
Hilary really had known very little of the whole Arian controversy before he was banished. Perhaps he supported Athanasius simply because he didn’t like their methods. But being exiled from his home and his duties gave him plenty of time to study and write. He learned everything he could about what the Arians said and what the orthodox Christians answered and then he began to write. Some of use may wonder at all the trouble over what may seem only words to us now. But Hilary wasn’t not fighting a war of words, but a battle for the eternal life of the souls who might hear the Arians and stop believing in the Son of God, their hope of salvation.
The death of Constantius in 361 ended the persecution of the orthodox Christians. Hilary died in 367 or 368 and was proclaimed a doctor of the Church in 1851.