The Book of Nature is a religious and philosophical concept originating in the Latin Middle Ages that explores the relationship between religion and science, which views nature as a book for knowledge and understanding. Early theologians, such as St. Paul,[1] believed the Book of Nature was a source of God's revelation to humankind. He believed that when read alongside sacred scripture, the "book" and the study of God's creations would lead to a knowledge of God himself. This type of revelation is often referred to as a general revelation. The concept corresponds to the early Greek philosophical belief that humans, as part of a coherent universe, are capable of understanding the design of the natural world through reason. Philosophers, theologians, and scholars frequently deploy the concept. The phrase was first used by Galileo, who used the term when writing about how "the book of nature [can become] readable and comprehensible".[2]