Saint Gregory of Nyssa
He is one of the group of Cappadocian Fathers and deserved to be called a "column of orthodoxy"
Together with his brother Basil the Great and his friend Gregory of Nazianzus, Saint Gregory Nyssen (c. 335-395) is one of the group of Cappadocian Fathers, united by their common geographical origin and, above all, by their theological and philosophical significance. Nyssen, the youngest of the three, was initially educated by his mother Emmelia and his sister Macrina the Younger, both of them saints. His veneration for the latter would later show in his Life of Macrina, where he remembers his sister's asceticism, proposing her as a model of virtue. In Gregory, however, the religious vocation was not immediately apparent: indeed, as a young man, he was more attracted to classical literature (of which he stressed the aspects he found compatible with Christianity) and rhetoric, so as to receive a fraternal reproach by the Gregory of Nazianzus, who criticised his preference of secular to sacred literature.
Around the year 360, after a spiritual crisis, a time when he felt most attracted to the world, Gregory went to Pontus, to stay in the monastery founded by Basil, where he lived for ten years. There he dedicated himself to the contemplative life under the guidance of his brother, whom he would define a "father and teacher", while indicating "Paul, John and the rest of the Apostles and prophets" as further references for his spiritual growth. At this time he conceived De Virginitate, a treaty in which he exalted consecrated virginity as the way to perfect union with God. He was then elected bishop of Nyssa and, due to his unflinching stand against heresy, he was unjustly accused of squandering ecclesiastical goods: deposed in 376 during a temporary absence, he was able to return to the episcopal see, to the jubilation of the faithful, only two years later, that is, at the death of emperor Valens, who supported Arianism.
Quite different was his relationship with the new emperor Theodosius, who proclaimed him "defender of the faith" and promulgated the edict of Thessalonica (380) by which Christianity, as the doctrine professed in the Nicene Creed, became the Empire's official religion. In the meantime, given the spread of the Macedonian heresy, which denied the divinity of the Holy Spirit, the First Council of Constantinople (convened in 381 by Theodosius himself) allowed the Church to officialise the Trinitarian doctrine already outlined in Nicea: Gregory’s contribution, like that of Basil (who had died two years earlier), spoke of the Trinity as "a substance in three persons", was among the most important, whereby the saint deserved to be called a "column of orthodoxy".
In addition to the various treaties refuting the main heresies of the time, Gregory wrote exegetical and moral works, letters, liturgical sermons, panegyrics, and was among the very first authors of antiquity to embark in a systematic criticism of slavery. His writings exude all his love for God and gratitude for His gift made to man: "Neither the sky was made in the image of God, nor the moon, nor the sun, nor the beauty of the stars, none other of the things that appear in creation. Only you [human soul] have been made the image of nature that dominates every intellect, the likeness of incorruptible beauty, the imprint of true divinity". To overcome sin, which ruins the soul and distances it from its ultimate goal, Saint Gregory indicated a sure way: “Through prayer we succeed in being with God. But anyone who is with God is far from the enemy. Prayer is a support and protection of charity, a brake on anger, an appeasement and the control of pride. Prayer is the custody of virginity, the protection of fidelity in marriage, the hope for those who are watching”.
Further reading:
Catechesis of Benedict XVI on Saint Gregory of Nyssa (general audience of 5th September 2007)