Liberal Protestantism developed in the 19th century out of a perceived need to adapt Christianity to a modern intellectual context. With the acceptance of
Charles Darwin's theory of
natural selection, some traditional Christian beliefs, such as parts of the
Genesis creation narrative, became difficult to defend. Unable to ground faith exclusively in an appeal to
scripture or the person of
Jesus Christ, liberals, according to theologian and intellectual historian
Alister McGrath, "sought to anchor that faith in common human experience, and interpret it in ways that made sense within the modern worldview." Beginning in Germany, liberal theology was influenced by several strands of thought, including the
Enlightenment's high view of human reason and
Pietism's emphasis on
religious experience and
interdenominational tolerance. The sources of religious authority recognized by liberal Protestants differed from conservative Protestants. Traditional Protestants understood the
Bible to be uniquely authoritative (
sola scriptura); all doctrine, teaching and the church itself derive authority from it. A traditional Protestant could therefore affirm that "what Scripture says, God says." Liberal Christians rejected the doctrine of
biblical inerrancy or
infallibility, Instead, liberals sought to understand the Bible through modern
biblical criticism, such as
historical criticism, that began to be used in the late 1700s to ask if biblical accounts were based on older texts or whether the
Gospels recorded the actual words of Jesus. The use of these methods of biblical interpretation led liberals to conclude that "none of the
New Testament writings can be said to be
apostolic in the sense in which it has been traditionally held to be so". This conclusion made
sola scriptura an untenable position. In its place, liberals identified the
historical Jesus as the "real
canon of the Christian church". German theologian
William Wrede wrote that "Like every other real science, New Testament Theology has its goal simply in itself, and is totally indifferent to all dogma and Systematic Theology". Theologian
Hermann Gunkel affirmed that "the spirit of historical investigation has now taken the place of a traditional doctrine of inspiration". Episcopal bishop
John Shelby Spong declared that the literal interpretation of the Bible is
heresy. The two groups also disagreed on the role of experience in confirming truth claims. Traditional Protestants believed scripture and
revelation always confirmed human experience and reason. For liberal Protestants, there were two ultimate sources of religious authority: the Christian experience of God as revealed in Jesus Christ and universal human experience. In other words, only an appeal to common human reason and experience could confirm the truth claims of Christianity. In general, liberal Christians are not concerned with the presence of biblical errors or contradictions. Liberals abandoned or reinterpreted traditional doctrines in light of recent knowledge. For example, the traditional doctrine of
original sin was rejected for being derived from
Augustine of Hippo, whose views on the New Testament were believed to have been distorted by his involvement with
Manichaeism.
Christology was also reinterpreted. Liberals stressed
Christ's humanity, and his divinity became "an affirmation of Jesus exemplifying qualities which humanity as a whole could hope to emulate". Liberal Christians sought to elevate Jesus'
humane teachings as a standard for a world civilization freed from
cultic traditions and traces of
traditionally pagan types of belief in the
supernatural. As a result, liberal Christians placed less emphasis on miraculous events associated with the life of Jesus than on his teachings. The debate over whether a belief in miracles was mere
superstition or essential to accepting the
divinity of Christ constituted a crisis within the 19th-century church, for which theological compromises were sought. Some liberals prefer to read Jesus' miracles as
metaphorical narratives for understanding the power of God. Not all theologians with liberal inclinations reject the possibility of miracles, but many reject the
polemicism that denial or affirmation entails. Nineteenth-century liberalism had an optimism about the future in which humanity would continue to achieve greater progress. This optimistic view of history was sometimes interpreted as building the
kingdom of God in the world.
Development The roots of liberal Christianity go back to the 16th century when Christians such as
Erasmus and the
Deists attempted to remove what they believed were the superstitious elements from Christianity and "leave only its essential teachings (rational love of God and humanity)".
Reformed theologian
Friedrich Schleiermacher (1768–1834) is often considered the father of liberal Protestantism. In response to
Romanticism's disillusionment with Enlightenment
rationalism, Schleiermacher argued that God could only be experienced through feeling, not reason. In Schleiermacher's theology, religion is a feeling of absolute dependence on God. Humanity is conscious of its own sin and its need of redemption, which can only be accomplished by Jesus Christ. For Schleiermacher, faith is experienced within a faith community, never in isolation. This meant that theology always reflects a particular religious context, which has opened Schleirmacher to charges of
relativism.
Albrecht Ritschl (1822–1889) disagreed with Schleiermacher's emphasis on feeling. He thought that religious belief should be based on history, specifically the historical events of the New Testament. When studied as history without regard to miraculous events, Ritschl believed the New Testament affirmed Jesus' divine mission. He rejected doctrines such as the
virgin birth of Jesus and the
Trinity. The Christian life for Ritschl was devoted to ethical activity and development, so he understood doctrines to be value judgments rather than assertions of facts. Influenced by the philosophy of
Immanuel Kant, Ritschl viewed "religion as the triumph of the spirit (or moral agent) over humanity's natural origins and environment." Ritschl's ideas would be taken up by others, and Ritschlianism would remain an important theological school within German Protestantism until World War I. Prominent followers of Ritschl include
Wilhelm Herrmann,
Julius Kaftan and
Adolf von Harnack. ==Liberal Catholicism==