Autocephaly recognized by some autocephalous Churches de jure: Autocephaly and canonicity recognized by Constantinople and 3 other autocephalous Churches: Spiritual independence recognized by Georgian Orthodox Church:
[2][3] He is canonized as a saint by the Coptic Orthodox Church, with his feast day on the 11th day of the month Abib (Epip) in the Coptic calendar.
Although he was active in Gaza (as he was quoted by Barsanuphius of Gaza), Isaiah was a product of the Egyptian monasticism which had developed in the 4th century in the Kellia (Cells) of the desert of Scetes, where he was first a monk during the early 400s.
He also became a close friend of Peter the Iberian and the two would meet periodically.
[citation needed] Excerpts of his writings are also included in the Philokalia.