The Venerable John Climacus is the author of The Ladder of Divine Ascent. John came to Mount Sinai as a sixteen-year-old youth and remained there, first as a novice, later as a recluse, and finally as abbot of Sinai until his eightieth year, when he reposed, in about the year 649. His biographer, the monk Daniel, says about him: “His body ascended the heights of Sinai, while his soul ascended the heights of heaven.” He remained under obedience to his spiritual father, Martyrius, for nineteen years. Anastasius of Sinai, seeing the young John, prophesied that he would become the abbot of Sinai. After the death of his spiritual father, John withdrew into a cave, where he lived a life of strict asceticism for twenty years.