Liberal Christianity in the context of "Christianity in the 19th century"

Unitarianism is a nontrinitarian sect of Christianity. Unitarians affirm the unitary nature of God as the singular and unique creator of the universe, believe that Jesus Christ was inspired by God in his moral teachings and that he is the savior of mankind, but he is not equal to God himself. Accordingly, Unitarians reject the Ecumenical Councils and ecumenical creeds, and sit outside traditional, mainstream Christianity.

Unitarianism was established in order to restore "primitive Christianity before later corruptions set in". Likewise, Unitarian Christians generally reject the doctrine of original sin. The churchmanship of Unitarianism may include liberal denominations or Unitarian Christian denominations that are more conservative, with the latter being known as biblical Unitarians.

Memorialism is the belief held by some Christian denominations that the elements of bread and wine (or grape juice) in the Eucharist (more often referred to as "the Lord's Supper" by memorialists) are purely symbolic representations of the body and blood of Jesus Christ, the feast being established only or primarily as a commemorative ceremony. The term comes from the Gospel of Luke 22:19: "Do this in remembrance of me", and the attendant interpretation that the Lord's Supper's chief purpose is to help the participant prayerfully remember Jesus and his sacrifice on the Cross, and symbolically renew commitment.

This viewpoint is commonly held by Anabaptists, the Plymouth Brethren, many Restorationist denominations (such as Jehovah's Witnesses), some Baptists, Pentecostals, and most Non-denominational churches, as well as those identifying with liberal Christianity.

Biblical infallibility is the belief that the Bible can be relied on entirely for guidance in faith and Christian living, providing accurate and trustworthy direction for salvation and spiritual practice.

Historically, Jewish and Christian interpreters have treated the Bible as trustworthy, though trust did not necessarily imply historical or scientific accuracy. The concept of biblical infallibility gained prominence in 19th- and early 20th-century Protestantism as a fundamentalist reaction against modernist trends in mainstream Christianity. In parallel, the Catholic Church developed the idea of papal infallibility, while evangelical churches emphasized the infallibility of Scripture. Both movements combined theological claims with ideological resistance to perceived erosion of traditional authority, reflecting a broader crisis in Western religious authority.

Friedrich Daniel Ernst Schleiermacher (/ˈʃlaɪərmɑːxər/; German: [ˈfʁiːdʁɪç ˈʃlaɪɐˌmaxɐ]; 21 November 1768 – 12 February 1834) was a German Reformed theologian, philosopher, and biblical scholar known for his attempt to reconcile the criticisms of the Enlightenment with traditional Protestant Christianity. He also became influential in the evolution of higher criticism, and his work forms part of the foundation of the modern field of hermeneutics. Because of his profound effect on subsequent Christian thought, he is often called the "Father of Modern Liberal Theology" and is considered an early leader in liberal Christianity. The neo-orthodoxy movement of the twentieth century, typically (though not without challenge) seen to be spearheaded by Karl Barth, was in many ways an attempt to challenge his influence. As a philosopher he was a leader of German Romanticism.

Christian fundamentalism, also known as fundamental Christianity or fundamentalist Christianity, is a religious movement emphasizing biblical literalism. In its modern form, it began in the late 19th and early 20th centuries among British and American Protestants as a reaction to theological liberalism and cultural modernism. Fundamentalists argued that 19th-century modernist theologians had misunderstood or rejected certain doctrines, especially biblical inerrancy, which they considered the fundamentals of the Christian faith.

Fundamentalists are almost always described as upholding beliefs in biblical infallibility and biblical inerrancy, in keeping with traditional Christian doctrines concerning biblical interpretation, the role of Jesus in the Bible, and the role of the church in society. Fundamentalists usually believe in a core of Christian beliefs, typically called the "Five Fundamentals". These arose from the Presbyterian Church issuance of "The Doctrinal Deliverance of 1910". Topics included are statements on the historical accuracy of the Bible and all of the events which are recorded in it as well as the Second Coming of Jesus Christ.

The Social Gospel is a social movement within Protestantism that aims to apply Christian ethics to social problems, especially issues of social justice such as economic inequality, poverty, alcoholism, crime, racial tensions, slums, unclean environment, child labor, lack of unionization, poor schools, and the dangers of war. It was most prominent in the early 20th-century United States and Canada.

Theologically, proponents of the movement emphasized living out the line from the Lord's Prayer (Matthew 6:10): 'Thy kingdom come, Thy will be done on earth as it is in heaven,' interpreting it as a call to address societal injustices. They typically were postmillennialist and believed the Second Coming could not happen until humankind rid itself of social evils by human effort. The Social Gospel was more popular among clergy than churches. Its leaders were predominantly associated with the liberal wing of the progressive movement and most were theologically liberal, although a few were also conservative when it came to their views on social issues. Washington Gladden and Walter Rauschenbusch were the two major founders of the movement.

Karl Barth (/bɑːrt, bɑːrθ/; Swiss Standard German: [bart]; (1886-05-10)10 May 1886 – (1968-12-10)10 December 1968) was a Swiss Reformed theologian. Barth is best known for his commentary The Epistle to the Romans, his involvement in the Confessing Church, including his authorship (except for a single phrase) of the Barmen Declaration, and especially his unfinished multi-volume theological summa the Church Dogmatics (published between 1932 and 1967). Barth's influence expanded well beyond the academic realm to mainstream culture, leading him to be featured on the cover of Time on 20 April 1962.

Like many Protestant theologians of his generation, Barth was educated in a liberal theology influenced by Adolf von Harnack, Friedrich Schleiermacher and others. His pastoral career began in the rural Swiss town of Safenwil, where he was known as the "Red Pastor from Safenwil". There he became increasingly disillusioned with the liberal Christianity in which he had been trained. This led him to write the first edition of his The Epistle to the Romans (a.k.a. Romans I), published in 1919, in which he resolved to read the New Testament differently.