St. Anastasius of Sinai

St. Anastasius of Sinai was a monk of the great monastery of St. Catherine at the foot of Mount Sinai in the seventh century, and one of the notable theologians and spiritual writers of the Christian East in that age. He traveled widely through Egypt, Syria, and Palestine, disputing with heretics and defending the orthodox faith in a region increasingly under the rule of Islam and troubled by lingering Christological divisions.

His best-known work is the Hodegos, or "Guide," a handbook composed to arm the faithful against the Monophysites and other errors and to defend the doctrine of the two natures of Christ, true God and true man, as taught by the Council of Chalcedon. He also wrote spiritual and exegetical works, including questions and answers on points of doctrine and morals and a commentary on the six days of creation, which shed light on the piety and problems of Eastern Christians of his day. He died about 700, and is venerated as a saint, his memory kept on 21 April.