Saint Gregory, the younger brother of Basil the Great, illustrious in speech and a zealot for the Orthodox Faith, was born in 331. His brother Basil was encouraged by their elder sister Macrina to prefer the service of God to a secular career (see July 19); Saint Gregory was moved in a similar way by his godly mother Emily, who, when Gregory was still a young man, implored him to attend a service in honor of the holy Forty Martyrs at her retreat at Annesi on the River Iris. Saint Gregory came at his mother's bidding, but being wearied with the journey, and feeling little zeal, he fell asleep during the service. The Forty Martyrs then appeared to him in a dream, threatening him and reproaching him for his slothfulness. After this he repented and became very diligent in the service of God.

Gregory became bishop in 372, and because of his Orthodoxy he was exiled in 374 by Valens, who was of one mind with the Arians. After the death of Valens in 378, Gregory was recalled to his throne by the Emperor Gratian. He attended the Local Council of Antioch, which sent him to visit the churches of Arabia and Palestine, which had been defiled and ravaged by Arianism. He attended the Second Ecumenical Council, which was assembled in Constantinople in 381. Having lived some sixty years and left behind many remarkable writings, he reposed about the year 395. The acts of the Seventh Ecumenical Council call him 'Father of Fathers."

The holy Hierarch Hilary was born of pagan parents in Gaul, and was trained in philosophy and rhetoric. At a time when paganism was still strong in Gaul, Saint Hilary understood the falsehood of polytheism, and became a Christian, and a great defender of his new Faith. About the year 350 he was ordained Bishop of Poitiers, when Arles and Milan were in the hands of the Arians and the Arian Constantius was sole Emperor. Like his contemporary Saint Athanasius, Saint Hilary's episcopate was one long struggle against the Arians. As bishop of Poitiers, Saint Hilary foresaw the future greatness of Martin (see Nov. 12), and attached him to himself. In 355, when required to agree to the condemnation of Saint Athanasius passed by the Council of Milan, Hilary wrote an epistle to Constantius convicting the wrongs done by the Arians and requesting, among other things, the restoration of the Orthodox bishops, including Athanasius. For this, Hilary was banished to Asia Minor, where he wrote his greatest work, On the Trinity. Saint Hilary returned to his see in 360, where Saint Martin sought him out again. It was this time that Saint Hilary blessed Martin to found a monastery near Poitiers, where Martin remained until being consecrated Bishop of Tours in 371. In his last years, Saint Hilary, strove for the deposition of Auxentius, the Arian Bishop of Milan, but by affecting an Orthodox confession Auxentius retained his see. Saint Hilary reposed in peace about the year 368. Auxentius died in 374 and was succeeded by Saint Ambrose, who continued Saint Hilary's battle against Arianism.

The holy virgin Nina was from Cappadocia. According to some, her father Zabulon was a friend of the holy Great Martyr George, whose father was a Cappadocian. The conversion of Georgia by Saint Nina is reported in the Church histories of Rufinus, Socrates, Sozomen, and Theodoret: Rufinus, writing less than a hundred years after Saint Nina, said that he heard the history in Jerusalem from a Georgian Prince named Bacurius. Saint Nina was taken captive by the Georgians (whom the Greek accounts call Iberians), and while in captivity she lived a very devout life of sobriety and virtue, praying unceasingly night and day; this drew the attention of the Georgians, and to all who asked her about her way of life, she preached the dispensation of Christ. When she healed by her prayer a certain woman's sick child, whom no one else had been able to help, the report of her came to the ears of the Queen of Georgia, who was herself gravely afflicted with an incurable malady. She asked that the captive women be brought to her, but Saint Nina declined out of modesty, so the Queen commanded them to carry her to Nina. Saint Nina healed her immediately, and the Queen returned home in joy. When she extolled Nina and her faith to the king, he gave her no heed, although she mentioned it to him often. But while hunting in the forest, he was shrouded with an impenetrable darkness in which he lost his way, became separated from his men, and fell into despair; he made a vow that if Christ should deliver him, he would worship him alone. The light of day straightway shone again, and the king fulfilled his vow. He and the Queen were instructed in the Faith by Saint Nina, and they with the whole Georgian nation became Christ's. The King also sent an embassy to Saint Constantine the Great, informing him of their conversion, and requesting that priests be sent to Georgia. Saint Nina reposed in peace in about the year 335. The above-mentioned Church historians speak of her without calling her Nina. She is celebrated in the Roman Martyrology on December 15 under the name Christina.

Because of the Apodosis of the Feast of Holy Theophany also on the 14th of January, the liturgical services to Saint Nina are transferred to January 13th.