St Hilary

From here:

Hilary went looking for the giftgiver. He was told many things about the divine -- many that we still hear today: that there were many Gods, that God didn't exist but all creation was the result of random acts of nature, that God existed but didn't really care for his creation, that God was in creatures or images. One look in his own soul told him these images of the divine were wrong. God had to be one because no creation could be as great as God. God had to be concerned with God's creation -- otherwise why create it?

At that point, 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."

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. "Although in exile we shall speak through these books, and the word of God, which cannot be bound, shall move about in freedom." The writings of his that still exist include On the Trinity, a commentary on the Gospel of Matthew, and a commentary on the Psalms. He tells us about the Trinity, "For one to attempt to speak of God in terms more precise than he himself has used: -- to undertake such a thing is to embark upon the boundless, to dare the incomprehensible. He fixed the names of His nature: Father, Son, and Holy Spirit. Whatever is sought over and above this is beyond the meaning of words, beyond the limits of perception, beyond the embrace of understanding."