St. Gregory of Nazianzus
Life: 330-389
Bio: After their studies at Athens, Gregory became Basil's fellow ascetic, living the monastic life together with him for a time in the hermitages of Pontus. His father ordained him presbyter of the Church of Nazianzus, and St. Basil consecrated him Bishop of Sasima (or Zansima), which was in the archdiocese of Caesarea. This consecration was a source of great sorrow to Gregory and a cause of misunderstanding between him and Basil, but his love for Basil remained unchanged, as can be plainly seen from his Funeral Oration on Saint Basil (Orat. XLIII).
About the year 379, St. Gregory came to the assistance of the Church of Constantinople, which had already been troubled for forty years by the Arians; by his supremely wise words and many labors he freed it from the corruption of heresy. He was elected archbishop of that city by the Second Ecumenical Council, which assembled there in 381, and condemned Macedonius, Archbishop of Constantinople, as an enemy of the Holy Spirit. When St. Gregory came to Constantinople, the Arians had taken all the churches, and he was forced to serve in a house chapel dedicated to St. Anastasia the Martyr. From there he began to preach his famous five sermons on the Trinity, called the Triadica. When he left Constantinople two years later, the Arians did not have one church left to them in the city. St. Meletius of Antioch, who was presiding over the Second Ecumenical Council, died in the course of it, and St. Gregory was chosen in his stead; there he distinguished himself in his expositions of dogmatic theology.
Having governed the Church until 382, he delivered his farewell speech-the Syntacterion, in which he demonstrated the Divinity of the Son-before 150 bishops and the Emperor Theodosius the Great. Also in this speech he requested, and received from all, permission to retire from the See of Constantinople. He returned to Nazianzus, where he lived to the end of his life. He reposed in the Lord in 391, having lived some sixty-two years.
Quote: ...the Good Shepherd, He who lays down His life for His sheep, came to seek for that which had strayed upon the mountains and the hills... and found the wanderer; and having found it, took it upon His shoulders... and having taken it, brought it back to the higher life; and having carried it back, numbered it amongst those who had never strayed (cf. Jn 10:11; Lk. 15:3-7). Because He lighted a candle--His own Flesh--and swept the house, cleansing the world from sin; and sought the piece of money, the Royal Image that was covered up by passions. And He calls together His Angel friends on the finding of the coin, and makes them sharers in His joy... (cf. Lk 15:8-10)
Books:  
On God and Man tanslated by Peter Gilbert
Gregory of Nazianzus by Brian E. Daley
Other websites:
Site 1
Site 2