Letters and Teaching
Isidore's principal legacy is his correspondence. Over two thousand of his letters survive, gathered in five books; the historian Nicephorus reported that he wrote as many as ten thousand in all. The letters fall into three broad concerns: dogma and the interpretation of Scripture, ecclesiastical and monastic discipline, and practical morality, and they offer reproach, counsel, encouragement, and consolation to a wide range of recipients.
In his reading of Scripture he favored the moral and spiritual sense of the text. He is recorded as holding that proficiency in good works matters more than skill in eloquent preaching, a conviction reflected in the practical and pastoral cast of his writing.