Christianity Study Guide

Second Coming

In Christian theology, refers to the anticipated return of Jesus Christ to Earth in glory. This event is expected to include the final judgment of humanity, the resurrection of the dead, and the establishment of God's kingdom in its fullness.

Paul

Originally known as Saul of Tarsus, Paul was an early Christian apostle who authored many New Testament epistles and played a crucial role in spreading Christianity throughout the Roman Empire. After a dramatic conversion experience, he became Christianity's most influential early missionary and theologian.

The New Testament

The second part of the Christian Bible, written primarily in Greek during the first century CE, containing 27 books including the Gospels, Acts, Epistles, and Revelation. It documents the life and teachings of Jesus, the early Christian church, and foundational Christian theology.

Original Sin

The doctrine that all humans inherit a state of sinfulness from Adam and Eve's disobedience in the Garden of Eden. This concept explains humanity's universal need for redemption and forms the basis for understanding salvation in Christian theology.

Salvation through Jesus Christ

The core Christian belief that humans can be saved from sin and death through faith in Jesus Christ's death and resurrection. This salvation is typically understood as a gift of divine grace, received through faith rather than earned through works.

Trinity

The central Christian doctrine that God exists as three distinct but inseparable persons

The Nicene Creed

A formal statement of Christian faith adopted at the Council of Nicaea in 325 CE and modified at Constantinople in 381 CE. This creed defines core Christian beliefs about the Trinity, the nature of Christ, and the church, serving as a foundational document for most Christian denominations.

Council of Nicaea

The first ecumenical council of the Christian church, convened by Emperor Constantine in 325 CE. This historic gathering addressed the Arian controversy about Christ's divine nature and established the Nicene Creed as orthodox Christian doctrine.

Arianism

An early Christian movement, declared heretical in 325 CE, that taught Jesus was created by and subordinate to God the Father. This controversy led to the Council of Nicaea and the formal articulation of Trinitarian doctrine.

The Great Schism (East-West Schism)

The formal split that occurred between Eastern Orthodox Christianity and Roman Catholicism in 1054 CE. This pivotal event in Christian history marked the division of Christendom into two distinct branches.

Martin Luther's 95 Theses and Protestant Reformation

A document criticizing Catholic Church practices, particularly the sale of indulgences, which sparked the Protestant Reformation. This movement led to a major split in Western Christianity, establishing Protestant denominations that emphasized scripture as the sole authority (sola scriptura), salvation through faith alone, and rejected papal authority.

The Nicene Creed

A formal statement of Christian faith adopted at the Council of Nicaea in 325 CE and modified at Constantinople in 381 CE. This creed defines core Christian beliefs about the Trinity, the nature of Christ, and the church, serving as a foundational document for most Christian denominations.

Council of Nicaea

The first ecumenical council of the Christian church, convened by Emperor Constantine in 325 CE. This historic gathering addressed the Arian controversy about Christ's divine nature and established the Nicene Creed as orthodox Christian doctrine.

Arian (Nature of Christ)

Jesus was a created being, subordinate to God the Father (Nature of Christ)

Nicene (Nature of Christ)

Jesus is fully divine, of the same substance (homoousios) as the Father (Nature of Christ)

Arian (View of the Trinity)

Rejected the concept of the Trinity as understood by Nicene theology (View of the Trinity)

Nicene (View of the Trinity)

Affirmed the Trinity with Father, Son, and Holy Spirit as coequal and coeternal (View of the Trinity)

Roman Catholic Church

The largest Christian denomination, led by the Pope as successor to Saint Peter and maintaining a hierarchical structure. It emphasizes tradition alongside scripture, seven sacraments, and the authority of the Magisterium in interpreting doctrine.

Eastern Orthodox Church

A communion of self-governing churches that separated from Rome in 1054, maintaining ancient traditions and liturgical practices. They emphasize theosis (divine transformation), the use of icons, and the authority of church councils.

Protestantism

A major branch of Christianity that emerged from the 16th-century Reformation, emphasizing biblical authority, salvation by faith alone, and the priesthood of all believers. It encompasses numerous denominations including Lutheran, Reformed, Anglican, Baptist, and Methodist churches.

Authority

Catholic/Orthodox emphasis on church tradition vs. Protestant focus on scripture alone

Sacraments

Seven in Catholic/Orthodox vs. typically two in Protestant traditions

Church Structure

Hierarchical in Catholic/Orthodox vs. varied in Protestant denominations

Salvation

Varying views on the role of faith, works, and grace. Catholics believe in salvation through faith and good works Protestants emphasize salvation through faith alone ("sola fide")

Worship Style

Liturgical (Catholic/Orthodox/some Protestant) vs. less formal (many Protestant)