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Religious Studies: Christianity

Religion 101


Jesus said to them, “I am the bread of life; whoever comes to me shall not hunger, and whoever believes in me shall never thirst.” (John 6:35)


Christianity is an Abrahamic monotheistic religion founded by and focused on Jesus Christ of Nazareth, born in Bethlehem, a town near Jerusalem in modern-day Palestine. The primary religious texts of Christians is the Bible, split into the Old Testament (comprised of the 24 books of the Jewish Tanakh), and the New Testament - Jesus' life and teachings. Christians believe that Jesus is the son of God, part of the Holy Trinity, Savior of the world, and the Messiah spoken about in Judaism. Christianity is the largest religion in the world, with over 2 billion Christians living in virtually every country due to colonialism, bringing Christian missionaries across the globe. Today, there are more than 45,000 different Christian sects, with more than 200 existing in the United States alone.

Christianity. (2001). In A. P. Iannone, Dictionary of world philosophy. Routledge. Credo Reference.

Founded between 4 BCE and 29 CE by Jesus Christ, Christianity gained traction through the dispersal of Jesus' disciples throughout the MENA (Middle East-North African) region, making its way into Europe to influence popular Western culture.

The story of Jesus is as follows:

Jesus Christ was born in Bethlehem in the Kingdom of Judah, which is modern-day Palestine, to a Jewish family. He was born by immaculate conception to the Virgin Mary after she was chosen by God. His adoptive father is Joseph, the husband of Mary. 

As Jesus aged, he began to preach the word of God and claimed he was the Jewish Messiah as well as the son of God. The Bible claims Jesus performed many miracles, which caused him to quickly gain followers. This angered the local Pharisees, who called Jesus a "false prophet" and persecuted him. Jesus was crucified on a cross, claiming in sacrificing himself he was saving the people of the world of their sins. After being buried in a tomb, Jesus rose from the dead after 3 days and ascended into heaven. Modern-day Christians base their understanding of the world, their own innate goodness and evil, and interactions with others on this origin story.

Belief in the Holy Bible: the Bible is a holy book, said to be the direct word of God, which "includes important scriptures that outline Jesus’s teachings, the lives and teachings of major prophets and disciples, and offer instructions for how Christians should live.Both Christians and Jews follow the Old Testament of the Bible, but Christians also embrace the New Testament."

Holidays: "The most important Christian holidays are Christmas (which celebrates the birth of Jesus) and Easter (which commemorates the resurrection of Jesus)."

Monotheistic: belief in one God - Jesus Christ

The Holy Trinity: The Father (God himself), the son (Jesus Christ) and the Holy Spirit. All three form the "Godhead", or the Holy Trinity.

Resurrection of Jesus: "[t]he essence of Christianity revolves around the life, death and Christian beliefs on the resurrection of Jesus. Christians believe God sent his son Jesus, the messiah, to save the world. They believe Jesus was crucified on a cross to offer the forgiveness of sins and was resurrected three days after his death before ascending to heaven."

The Second Coming: "Christians contend that Jesus will return to earth again in what’s known as the Second Coming."


Catholicism is the largest branch of Christianity, with approximately 1.3 billion Catholics living around the globe. It follows the basic premises of Christianity: monotheism, belief in the Holy Trinity, and belief in the Bible. Also known as the Catholic Church, Catholicism is considered by many Christians to be the first consolidated iteration of Christianity, founded by Saint Peter. Catholics tend to focus on three aspects of Christianity:  "importance of human works, God’s grace, and reception of sacraments for redemption."

"In its etymology, the word Catholic derives from Greek katholikos and Latin catholicos, signifying the universal nature of Christian tradition and all-embracing character of the Catholic Church." Catholics believe that the Pope is the head of the Catholic Church globally and is considered especially close to God, with the unique ability to interpret the word of God and proclaim truths about Christianity due to his linkage to the succession of Saint Peter.

The hierarchy of the Catholic Church is universal, and looks like this:

  • The Pope, Archbishops, bishops, priests and deacons.

 This focus on hierarchy in the church was (and is) the source of much contention between Catholics and newer sects of Christianity.

Catholicism has certain rites called sacraments, and there are 7 of them: Baptism, Confirmation, Eucharist, penance, marriage, ordination, and anointing of the sick. "The seven sacraments are essential for the participation of Catholics in the life of the church, society, and personal religious well-being, bringing to all these aspects of divine complicity."

Giordan, G. (2020). Catholicism. In A. Possamai, & A. J. Blasi (Eds.), The SAGE encyclopedia of the sociology of religion. Sage UK. Credo Reference.


Protestantism is a catch-all term for the form of Christian faith and practice that originated with the principles of the Protestant Reformation, started by German priest Martin Luther. As a general term, Protestantism is mostly used to show difference from the other major Christian faiths: Roman Catholicism and Eastern Orthodoxy. In general, Protestants follow the basic tenants of Christianity. However, they also typically reject the rigid hierarchy present in Roman Catholicism (no intermediaries between the practitioner and God), focus on the wholeness and singular truth of the Bible, a belief that all Christian believers are part of a "universal priesthood", and a belief in "sole fide", or by faith in God alone a person reaches salvation - salvation is not reached by good works. Today, almost half of all Christians in the United States are Protestants.

Branches and Sects

  • Adventists
  • Anabaptists 
  • Baptists
  • Calvinism
  • Congregationalism
  • Lutheranism
  • Methodism
  • Pentecostalism
  • Presbyterianism
  • Puritanism 
  • spiritism
  • Unitarianism

Protestantism. (2018). In P. Lagasse, & Columbia University, The Columbia encyclopedia (8th ed.). Columbia University Press. Credo Reference.


Orthodox or Eastern Orthodox or Greek Orthodoxy is the second largest Christian Church, after Catholicism. The Orthodox Church touts over 200 million believers worldwide, and believes in the same basic principles as Catholic and Protestant believers do. The primary beliefs that differentiate the Eastern Orthodox Church include belief that personal Christian belief and the Church are inseparable (in a similar vein to Catholicism), a focus on vibrant iconography in churches and places of worship, and a rejection of specific Catholic beliefs and traditions, like purgatory.

Like Catholics, Orthodox Christians follow the 7 sacraments:

  • Baptism, Confirmation, Eucharist, penance, marriage, ordination, and anointing of the sick.


Orthodox Christianity also follows a hierarchical structure similar to Catholicism, but removes the notion that the Pope is a virtually infallible leader of the religion. In fact, Orthodox Christians believe that all bishops are similar in authority, and have similar levels of closeness to God.

The Greek hierarchy is made up of the following: bishop, priest, and deacon.

Papanikolaou, A. (2011). Orthodox theology. In I. A. McFarland, D. A. S. Fergusson, K. Kilby, & et. al. (Eds.), Cambridge dictionary of Christian theology. Cambridge University Press. Credo Reference.

Jehovah's Witnesses: religious movement founded in Pennsylvania by Charles Russell focused primarily on apocalyptic passages in the Bible.

  • Official site for Jehovah's Witness beliefs and doctrine

Mormonism: aka Church of Latter Day Saints; a religion founded by Joseph Smith, based on both the Bible and the Book of Mormon.

Seventh Day Adventists: 19th century US Christian religious movement focused on Christ's Second Coming (or Advent).

  • Adventist: Official website for the Seventh-day Adventist Church

Thomasson, G. C. (2021). Mormonism. In S. Holland (Ed.), Encyclopedia of American Studies. Johns Hopkins University Press.

Encyclopaedia Britannica. (2017). Jehovah's witness. In Britannica Concise Encyclopedia. Britannica Digital Learning.

Van Bemmelen, P. M. (2015). Christianity: Seventh-day Adventists. In Gale (Ed.), Worldmark Encyclopedia of Religious Practices. Gale.


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