St. Gregory of Nyssa (335 - 394) was from a Christian family in Cappadocia, Asia. His brother was the famous St. Basil the Great who appointed him bishop of the town of Nyssa in 371. There he helped defend the Nicene Creed.

He wrote a number of mystical Christian books, of which The Life of Moses is perhaps the most important. In this book St. Gregory describes the life of Moses as it appears in the book of Exodus and Numbers. Then he explains the events literally and then spiritually, The reader is encouraged to walk the same virtuous steps as Moses and to ultimately ascend the holy mountain becoming a friend of God.