His works include the _Sacramentary_, which determined the language and the form of the Liturgy, a series of _Dialogues_, and a _Pastoral_, in which were collected a series of discourses planned to regulate the vocation, life, and doctrines of the pastors. Of this book, Ozanam says that it gave form and life to the entire hierarchical body. Then came a series of commentaries on the Scriptures, followed by no less than thirty-five books called _Moralia_, which were commentaries on the Book of Job. His last important production was a series of _Epistles_, comprised in thirteen volumes. He may possibly have been the most voluminous author since classic times, and his books had the special advantage of reaching circles of readers who were waiting for them, and of being distributed through the already extended machinery of the Church. Another important ecclesiastical author of the same generation was Isidore, Bishop of Seville. The Spanish Liturgy compiled by him and known as the Mozarabic, survived the ruin of the Visigothic Church and was thought by the great Cardinal Ximenes worthy of resuscitation. Isidore also wrote a history of the Goths and a translation of the philosophy of Aristotle. He may be considered as the first scholar to introduce to Europe of the Middle Ages the teachings of Greek philosophy. His greatest undertaking was, however, in the form of an encyclopædia, treating, under the heading of the Seven Liberal Arts, of all the learning that was within his reach. It was entitled _Twenty Books of Etymologies_, or _The Origin of Things_, and included in its volumes a number of classical fragments which, without the care of its editor, would probably have perished forever. Isidore is the first Christian who arranged and edited for Christians the literature of antiquity. He died in 636, but the incentive that he had given to learning and to literature survived him in a numerous group of disciples.[29] Among Isidore’s pupils was King Sisebut, whose interest in scholarship caused him to endow liberally a number of the Spanish monasteries.