Gregory’s father was an eminent official at the court of Emperor Andronicus II Palaeologus. The gifted Gregory, completing his secular studies, did not want to enter the service of the imperial court, but withdrew to the Holy Mountain and was tonsured a monk. He lived a life of asceticism in the Monastery of Vatopedi and the Great Lavra. He led the struggle against the heretic Barlaam and finally defeated him. He was consecrated as Metropolitan of Thessalonica in the year 1347 A.D. He is glorified as an ascetic, a theologian, a hierarch and a miracle-worker. The Most-holy Theotokos, St. John the Theologian, St. Demetrius, St. Anthony the Great, St. John Chrysostom and angels of God appeared to him at different times. He governed the Church in Thessalonica for thirteen years, of which he spent one year in slavery under the Saracens in Asia. He entered peacefully into rest in the year 1360 A.D, and took up his habitation in the Kingdom of Christ. His relics repose in Thessalonica, where a beautiful church is dedicated to him.