Didymus the Blind

Didymus the Blind (c. 313 - c. 398) was an ecclesiastical writer of Alexandria . He became blind at the age of four, before he had learned to read, but nevertheless succeeded in mastering the whole corpus of the sciences then known. On entering the service of the Church he was placed at the head of the Catechetical school in Alexandria , where he lived and worked until almost the close of the fourth century. Among his pupils were Jerome and Rufinus.
He was a loyal follower of Origen , though boldly opposed to Arian and Macedonian teachings. His surviving writings show a remarkable knowledge of scripture and have distinct value as theological literature. Among them are the De Trinitate , De Spiritu Sancto (Jerome's Latin translation), Adversus Manichaeos , and notes and expositions of various books, especially the Psalms and the Catholic Epistles .
His feast day is October 18 / 31.

Source: OrthodoxWiki