Isaiah the Solitary
Isaiah the Solitary, also known as Isaiah of Gaza, Isaias the Solitary, Abba Isaiah, or possibly also Isaiah of Scetis, was a Christian ascetic and monastic writer known from the Sayings of [the Desert Fathers] and various Palestinian Miaphysite sources. He is canonized as a saint by the Coptic Orthodox Church, with his feast day on the 11th day of the month Abib in the Coptic calendar.
His work "On Guarding the Intellect" can be found in the Philokalia.
Life
Although he was active in Gaza, Isaiah was a product of the Egyptian monasticism which had developed in the 4th century in the Kellia of the desert of Scetes, where he was first a monk during the early 400s. There, he lived on a mountain and moved then to Palestine.Much of Isaiah's writings were instructive for monks and solitaries. Very few of his writings are extant, as the majority of them have been destroyed by Muslims.
Isaiah was also influential in bringing Christianity to Palestine. He was also in contact with intellectuals of the city of Gaza such as Aeneas of Gaza, one of the members of the Rhetorical School of Gaza, who consulted him in regard to the philosophical writings of Plato, Aristotle and Plontius. He also became a close friend of Peter the Iberian and the two would meet periodically.
He died as a hermit in a monastery near Gaza on 11 August 491.
Writings
Many of Isaiah's works have been lost. The Asceticon, a collection of about 30 discourses on Christian asceticism, was especially popular in the Eastern Orthodox monastic tradition, and has survived in many translations in Syriac, Coptic, Ethiopic, Armenian, Arabic, and Georgian. The Syriac version of his Asceticon, which is only a partial translation of the original Greek text, has been translated into French.Excerpts of his writings are also included in the Philokalia. His work the 'Book on Religious Exercises and Quiet' is also available in English.