Similarly, the canonization of the New Testament by the Early Christian Church became an important aspect in the formation of the separate religious identity for Christianity. Ecclesiastical authorities used the acceptance or rejection of specific scriptural books as a major indicator of group identity, and it played a role in the determination of excommunications in Christianity and in "cherem" in the Jewish tradition. Church father Origen (184-253 CE), due to his familiarity with reading and interpreting Hellenistic literature, taught that some parts of the Bible ought to be interpreted non-literally. Concerning the Genesis account of creation, he wrote: "who is so silly as to believe that God ... planted a paradise eastward in Eden, and set in it a visible and palpable tree of life ... [and] anyone who tasted its fruit with his bodily teeth would gain life?" He also believed that such hermeneutics should be applied to the gospel accounts as well. Church father Augustine of Hippo (354–430 CE) wrote of the need for reason in interpreting Jewish and Christian scripture, and of much of the Book of Genesis being an extended metaphor. But Augustine also implicitly accepted the literalism of the creation of Adam and Eve, and explicitly accepted the literalism of the virginity of Jesus's mother Mary. In the Reformation, Martin Luther (1483–1546 CE) separated the biblical apocrypha from the rest of the Old Testament books in his Bible, reflecting scholarly doubts that had continued for centuries, and the Westminster Confession of 1646 demoted them to a status that denied their canonicity. American Protestant literalists and biblical inerrantists have adopted this smaller Protestant Bible as a work not merely inspired by God but, in fact, representing the Word of God without possibility of error or contradiction. Biblical literalism first became an issue in the 18th century, enough so for Diderot to mention it in his "Encyclopédie". Karen Armstrong sees "[p]reoccupation with literal truth" as "a product of the scientific revolution". The vast majority of evangelical and fundamentalist Christians regard the Biblical text as clear, and believe that the average person may understand the basic meaning and teachings of the Bible. Such Christians often refer to the teachings of the Bible rather than to the process of interpretation itself. The doctrine of clarity of the text does not mean that no interpretative principles are necessary, or that there is no gap between the culture in which the Bible was written and the culture of a modern reader. On the contrary, exegetical and interpretative principles come into play as part of the process of closing that cultural gap.