Gregory Palamas was a monk of Mount Athos in Greece and later the Archbishop of Thessalonica known as a preeminent theologian of Hesychasm. The teachings embodied in his writings defending Hesychasm against the attack of Barlaam are sometimes referred to as Palamism, his followers as Palamites. Palamas is venerated as a Saint in the Eastern Orthodox Church. Some Byzantine Catholic Churches, which are in communion with Rome, venerate him in the liturgy, and he has been called a saint and has been repeatedly cited as a great theological writer by Pope John Paul II. Some of his writings are collected in the Philokalia. The second Sunday of the Great Lent is called the Sunday of Gregory Palamas in those Churches that commemorate him according to the Byzantine Rite. He also has a feast day on November 14.
Gregory was born in Constantinople in the year 1296. His father was a courtier of the Byzantine Emperor Andronikos II Palaiologos , but he died soon after Gregory was born. The Emperor himself took part in the raising and education of the fatherless boy. The Emperor had hoped that the gifted Gregory would devote himself to government service. St Gregory received his secular philosophical training from Theodore Metochites.
Source: Wikipedia