This Glossary is designed not as an academic theological dictionary but as a practical tool for the students of the class "Global Christianities – Past and Present” and all visitors of the webpage to easily navigate the suggested resources. It serves as a quick reference, helping beginners familiarize themselves with the fundamental concepts and key terms of Christianity in an accessible way without overwhelming detail. Bibliography and further materials can be found under our Themes and Resources page.
African Independent Churches: Also known as African initiated or African Indigenous Churches. These churches are Christian churches founded in Africa by Africans and for Africans from the late nineteenth century to the early twentieth century, often outside the control of missionary or colonial churches. These churches incorporate local languages, customs, and leadership styles, and are a testament to African agency in religious life. Examples include Ethiopian Churches, Zionist Churches, and Aladura Pentecostal Churches.
Apocalypse: Derived from the Greek word apokalypsis ("revelation" or "unveiling"). It refers to both the last book of the New Testament and the eschatological events it describes, including the Second Coming of Christ, the ultimate battle between good and evil, and the final establishment of God's eternal kingdom.
Apocryphon: Derived from the Greek word for "hidden", it signifies non-canonical religious texts. These writings are typically pseudodepigrapha (falsely attributed to apostles or other authoritative figures) to lend them legitimacy. The New Testament apocrypha were often associated with Gnostic traditions, while the Old Testament ones are part of the Septuagint.
Apostle: Derived from the Greek word apostolos (“delegate” or “ambassador”). It signifies the students and followers of Jesus Christ who were appointed to evangelize and convert people worldwide. The first twelve were appointed by Jesus himself after his ascension to Heaven. Other apostles from the times of the New Testament are first of all Paul as apostle of the Gentiles but also Barnabas, James et alii. The term “Apostle” is also associated with various saints throughout the centuries, called isapostles (equal-to-Apostles, such as Thecla or Olga of Kiev).
Apostolic Age: The period in early Christian history when Jesus’ disciples, the apostles, were alive, spread the message of Christ. It began after the death, resurrection, and ascension (30 CE) and lasted until the death of the last apostle, John (100 CE).
Asceticism: see Monasticism.
Baptism: The Christian sacrament of initiation, mandatory for becoming a member of a congregation and partaking in all other sacraments. Typically performed through the sprinkling of or immersion in water, it is conducted only once in a lifetime. Most denominations perform paedobaptisms(infant baptisms). Accepting the validity of baptisms among all those denominations using a Trinitarian formula is common.
Bible: The sacred Scriptures of Christianity, consisting of two collections of books, the Old and New Testaments. The Old Testament includes the Hebrew scriptures, while the books of the New Testament contain the life and teachings of Jesus Christ. The term "Bible" is derived from the Greek biblia (books), indicating that it is a collection of writings rather than a single book.
Black Church: Christian congregations founded by and for African Americans, emerging mainly in the eighteenth and nineteenth centuries in the United States as spaces of worship, communities and social activism. The African Methodist Episcopal Church and the National Baptist Convention are examples of black churches.
Canon: An official list of texts accepted as legitimate by a community. In religious communities, the formal books that are accepted as sacred are referred to as the canon. In Christianity, the canon refers to the books recognized as legitimate and divinely inspired in the Old and New Testaments. The Christian canon is diverse across traditions. Certain books are accepted by some denominations while they are rejected by others.
Catechumen: A person receiving instructions about the basic doctrines and disciplines– preparing the person for baptism and reception into the Church. Catechumen holding the official status of a learner or candidate, participating in certain rites but not yet fully admitted to the sacramental life of the Church.
Colonial Missions: Missions conducted in association with European colonial powers, religious conversions often intersected with empire-building. Catholic orders like the Jesuits, Franciscans, Dominicans, and Augustinians were central to early missions in Asia, Africa, and the Americas, but various Christian denominations such as Anglican, Lutheran, Reformed, Methodist, Baptist, and Moravian played an important role in spreading Christianity worldwide.
Confirmation: Also called Chrismation, confirmation is a sacrament in many Christian denominations in which a baptized person is anointed with oil and receives the Holy Spirit (see Holy Trinity), confirming their faith. In Catholicism, confirmation symbolizes spiritual maturity, often performed during adolescence, while in the Orthodox Church, it is performed immediately after baptism.
Charismatic Christianity: A form of Christianity that emphasizes the active role of the Holy Spirit (see Holy Trinity) in the lives of believers. This is exhibited in practices that manifest supernatural occurrences (e.g., speaking in tongues, prophesy, healing, and handling snakes). While charismatic elements may exist in traditional churches, this term is typically associated with certain branches of Protestantism, most notably Pentecostalism.
Councils: Going back to the biblical Council of Jerusalem or Apostolic Council (Acts 15) which took place c. In the 50 CE, meetings of bishops became an accepted form of governing the Church. Particularly since the fourth century, councils became a common means of deciding about doctrinal questions, introducing disciplinary canons, and in general regulating the life of the Church. The first so-called ecumenical council, the Council of Nicaea (325 CE), stipulated that bishops were supposed to meet twice a year for provincial councils.
Deuterocanonical: Refers to books or writings that are considered canonical by some Christian traditions, particularly the Catholic and Orthodox Churches, but are not included in the Hebrew Bible or accepted by most Protestant denominations. These books are part of the Septuagint.
Diaspora Missions: Missionary work aimed at people who have migrated or been displaced from their homeland., The Catholic Church’s mission to Filipino communities in the United States is an example.
Ecumenical councils: were convened by the Roman/Byzantine emperor and their ecclesiastical decisions were turned into state law. The first seven ecumenical councils accepted by Catholicism as well as Orthodoxy are: the Council of Nicaea (325 CE), the First Council of Constantinople (381 CE), the Council of Ephesus (431 CE at which the later Assyrian Church of the East split), the Council of Chalcedon (451 CE at which the Oriental Orthodox Churches split), the Second Council of Constantinople (553 CE), the Third Council of Constantinople (680-1 CE), and the Second Council of Nicaea (787 CE).
Ecumenism: A movement aimed at promoting unity and cooperation among different Christian denominations. It seeks to overcome historical divisions, theological disagreements, and institutional separations that have fragmented Christianity over centuries.
Eucharist: Derived from the Greek word for “thanksgiving” and also known as Holy Communion, it is a Christian sacrament in which bread and wine are consecrated and consumed, symbolizing the flesh and blood of Jesus Christ. Originating from the Last Supper, the Eucharist serves as the central act of worship, signifying the sacrifice of Christ and the believer's union with Him. In the traditional Churches, the bread and the wine are believed to have been literally transformed into Jesus’ flesh and blood through the process of transubstantiation.
Evangelization: The act of spreading the Christian Gospel with the intention of converting individuals or communities to Christianity. It involves preaching, teaching, and witness through word and deed, and has taken many forms throughout history – from personal testimony to organized missionary campaigns across the globe.
Exegesis: The critical interpretation and explanation of biblical texts. It focuses on analyzing the historical, cultural, linguistic, and theological context to understand the original meaning and intent of the scriptures.
Filioque: Meaning “and from the Son,” the Filioque is one of the most fundamental theological differences between the Catholic and Orthodox Churches. It refers to the belief that the Holy Spirit proceeds not only from the Father but also from Jesus Christ. This phrase was added to the Nicene Creed by the Western Church around the 6th century. The Orthodox (as well as the Oriental Orthodox and Assyrian of the East) Churches reject this addition, arguing that it disrupts the balance of the Holy Trinity.
God: see Holy Trinity.
Gospel: Originally "Evangelion" (Greek: "good news"), this term initially refers to the four canonical books of the New Testament, the gospels accepted to have been written by Matthew, Mark, Luke, and John, recounting the life and teachings of Jesus Christ. These texts are the foundation of Christian doctrine and practice. In addition, there are also apocryphal gospels (such as the Gospel of Thomas, Gospel of Mary, and Gospel of Judas) that are not recognized as part of the New Testament canon.
Heaven: In Christian theology, Heaven is seen as the ultimate goal of human existence, symbolizing the restoration of the direct relationship with God as intended at creation. While the concept of heaven is central in most Christian denominations, its interpretation varies, with some viewing it more metaphorically and others more literally. Heaven is commonly believed to be the destination for those who are saved through their faith after the second coming of Jesus Christ and the final judgment.
Hell: In Christianity, hell represents spiritual suffering and separation from God. It is commonly associated with fire, signifying the eternal pain, grief, and separation from God's grace. The Christian hell is the consequence of sin, while the imagery of fire symbolizes the soul's decay and separation from the love of God.
Hermeneutics: The theory of interpretation of the Scriptures, focused on how we understand the Bible today. It addresses the guiding principles for interpreting difficult passages and involves broader theological and philosophical frameworks that influence how the Bible is read and applied in various contexts.
Holy Orders: A sacrament in Christian traditions that grants the authority to serve in leading roles within the Church. This includes ordaining deacons, priests, and bishops. Holy Orders is considered a sacred vocation, providing the grace to exercise specific ministerial roles and responsibilities.
Holy Trinity: The Holy Trinity in Christianity refers to the doctrine of one God in three persons or hypostases: the Father, the Son (Jesus Christ), and the Holy Spirit, each being one complete God themselves. These three hypostases are coequal, consubstantial, and undivided, sharing the same divine essence (homoousion) according to the Nicene Creed. The concept of the Holy Trinity is one of the most theologically challenging dogmas of Christianity, and it is generally considered to be beyond human intellectual capacities.
Jesuits (Society of Jesus): A Catholic religious order founded in 1540 by Ignatius of Loyola during the so-called Counter-Reformation. The Jesuits, known for their education, played a major role in Catholic counter-reformatory renewal in Europe as well as spreading Christianity to Asia, Africa, and the Americas, often engaging deeply with local languages and cultures (accommodatio) while also supporting European colonial interests.
Jesus Christ: Jesus Christ is hypostasis of the Holy Trinity, being the Son of the Father. While it is believed that his existence precedes time, he was born as a human in Bethlehem at the beginning of the common era. After preaching and performing miracles in the area of Galilee, he was persecuted by the Jews for blasphemy and was executed by the Roman governor by crucifixion in Jerusalem. According to Christian belief, three days after his death, he was bodily resurrected and spent 40 days with his students before his final ascension to Heaven. Christians expect him to have a second coming during the apocalypse. Jesus Christ is central to Christian denominations, with varying beliefs about the balance between his divinity and humanity.
Liturgy: The structured public worship of the Christian Church. While it differs significantly among denominations, a liturgy usually includes prayers, scripture readings, hymns, and sacramental rituals. In Catholicism and Eastern Christianity, the ultimate objective of each liturgy is to consume the Eucharist.
Martyr: Derived from the Greek word martys (“witness”), martyrs are the saints who were tortured and executed for confessing their faith in Jesus Christ. They are venerated by Christian communities or churches and celebrated each year, usually on the day of their death. In the early days of the Church, special shrines were built over their graves, called martyria. Their remains, called relics, have been worshiped for centuries after their death. Martyrs after the Diocletianic persecution in the early 4th century are often referred to as neomartyrs. This includes those under Islamic rule since the 7th century, during periods of colonialism, under the Ottoman Empire, or in totalitarian regimes.
Megachurches: Protestant/evangelical congregations with weekly attendance over 2,000 people (while congregations with more than 10.000 attendees per service have been called gigachurches), often featuring contemporary worship, multimedia services, and extensive community programs. While the first megachurches were established in the 19th century, they particularly became widespread towards the end of the 20th century – in the US but also in Africa, Asia and Australia.
Mission/s : Organized efforts by a religious group to spread their faith, provide spiritual guidance, and engage in social or humanitarian work, often in regions or among communities where the religion is not yet established; for example, Jesuit missions in Asia, Africa and South America in the sixteenth century.
Monasticism: A regulated way of living practiced by Christian individuals who choose to withdraw from society. Monks and nuns live ascetic lives, reducing or avoiding indulgences (particularly concerning food but also sleep), sometimes to the extreme. Monasticism began in 3rd/4th century Egypt with Antony the Great and Pachomios the Great. It spread widely during the Middle Ages and remains significant in traditional denominations today. Practices vary across traditions: some monks and nuns live in complete seclusion focused on prayer, especially in the East, while others have been active in education and missionary work for the Catholic Church, also developing distinct spiritualities within various monastic and mendicant orders (Benedictines, Franciscans, Jesuits, et alii).
Nicene Creed: Statement of belief of the Holy Trinity, first drafted by the Council of Nicaea in 325. Christian tradition believes that 318 “Church Fathers”, that is, bishops, convened in what is today Iznik/Turkiye, and issued this creed, which is almost universally accepted among Christians who believe in a Trinitarian God; those Christians who did not believe in the consubstantial Trinity issued a different creed (Councils of Ariminum in 359). Today, Unitarians, for example, do not believe in a Trinitarian God and deny Christ’s divinity.
Pastor: Literally meaning “shepherd,” a pastor is a Christian leader entrusted with spiritually guiding a congregation. Rooted in the biblical image of a shepherd, a pastor preaches the Gospels and administers sacraments. Most Protestant denominations have pastors instead of sacramental clergy.
Pentecostalism: Christian movement that originated in the early twentieth century, which emphasizes the work of the Holy Spirit, spiritual gifts (such as speaking in tongues and healing), and personal conversion. From the early twentieth century, Pentecostalism spread rapidly, especially in Africa, Latin America, and Asia, often through dynamic, locally led churches that focused on direct spiritual experience rather than formal theological training or colonial structures.
Pentateuch: Also known as the Torah, refers to the first five books of the Old Testament: Genesis, Exodus, Leviticus, Numbers, and Deuteronomy. These books form the foundation of both Jewish and Christian Scriptures. They contain the creation story, laws, and the early history of Israel.
Priest: A priest is a religious leader who performs sacred rituals, mediates between God and the people, and administers sacraments. In traditional churches, that is, churches that delineate themselves to the times of the apostles, each priest is considered to be linked to the original apostles by a line of succession. Priesthood is organized within a hierarchical clergy, depending on the size of the regions they oversee. Most protestant traditions reject sacramental priesthood.
Proselytism: The act of attempting to convert people to another religion, often with a pejorative connotation due to coercive or unethical methods in converting people.
Prophet: From the Greek “the one foretelling,” prophets are enlightened individuals chosen to deliver God’s messages and warnings during tumultuous times. They appear mainly in the Old Testament, calling the Jews back to repentance, and they have foreseen the coming of the Messiah. In traditional Churches, John the Baptist is considered to be the last of the prophets since, after the incarnation of Jesus Christ, there was no need for prophets anymore. However, other denominations and Charismatic Christian cults recognize prophetic gifts in people to this day.
Purgatory: A temporary afterlife state for those who died in God’s grace, but whose souls have not been fully prepared for Heaven during their lifetime. It involves a purifying fire, which cleanses the soul through suffering. While believing in an intermediate state of the souls before final judgment and their allocation between Heaven and Hell is common for various Christian denominations, Purgatory is an exclusively Catholic doctrine established in the High and Late Middle Ages.
Puritanism: A sixteenth – seventeenth century Protestant movement, focusing on piety and purity of worship, but without any monolithic theological understanding or ecclesiological concept. It originally intended to reform the Church of England – that is, to make it a properly “Protestant” Church to “purify” it from any Catholic practices. However, Puritanism became particularly prominent in the North American colonies in the 17th century because many Protestant dissidents from Europe, unsuccessful with Puritan reforms at home, had fled here.
Reformation: 16th-century theological movement in western Europe that sought to fix the perceived wrongdoings of and corruption in the Catholic Church. The early leaders of the reformation like Martin Luther and Huldrych Zwingli focused on the authority of the Scriptures, and Luther’s translation of the Bible into German also prepared the ground for its study in vernacular languages. Different doctrinal beliefs – like Predestination (all events have been willed by God) – and rejection of sacramental priesthood and hierarchical clergy resulted in a lasting division of Christendom. Today, Protestant Churches (Anglicans, Episcopalians, Calvinists or Reformed, Lutherans, Methodists, Presbyterians, et alii) are the second largest group of Christians after Catholics.
Relics: Physical remains (especially bones) and objects (for example, the so-called Holy Robe of Christ in Trier) associated with holy figures, such as Jesus Christ, the Virgin Mary, martyrs, and saints. In traditional churches, they are deeply cherished: churches are built to house them, feasts are held in their honour, and processions are organized around them. Believers see them as vessels of divine grace, capable of miracles such as healing illnesses.
Resurrection: Signifying the reconnection of the soul and the dead body, which results in returning to life, resurrection is one of the central dogmas of Christianity. Following the bodily resurrection of Jesus Christ, all people are expected to be resurrected after his second coming for their final judgment. Resurrection is also described in the Gospels as a miracle performed by Jesus three days after his crucifixion and death. The physical attributes of the resurrected body resemble those of a living person, only with different physical properties. Finally, there are accounts of resurrections in the New Testament performed by Jesus before his own.
Reverend: In early modern times, honorific terms to address clerics – like “(the very) reverend” in English – have been developed; other European languages have similar designations (monsignore, monseigneur, Hochwürden, etc.).
Revival (religious): A renewed interest in religion or an outpouring of spiritual fervor, often connected with missionary expansion or mass conversions.
Sacraments: Sacred Christian rituals through which believers receive divine grace and are essential for spiritual life. They usually mark significant milestones in the lifetime of Christians, establishing their position in a congregation. Catholic, Orthodox and Oriental Orthodox Churches have seven sacraments: Baptism, Eucharist, Confirmation, Penance, Anointing of the sick, Matrimony, and Holy Orders. The Assyrian Church of the East also has seven sacraments, but includes the Holy Leaven (powder added to the sacramental bread, supposedly going back to the Last Supper) and the Sign of the Cross instead of Matrimony and the Anointing of the sick. Most Protestant traditions recognize less sacraments, often only two: Baptism and Eucharist.
Saint: A person who lived a holy life and is believed to have been granted God’s grace and thus can mediate with him after death on behalf of other Christians. There are various kinds of saints: martyrs, clergymen who fought for the dogma, monks who lived an ascetic life, et alii. Their veneration involves an official ecclesiastical process that gradually developed over centuries, often prompted by reports of miraculous events. Christians show their respect to saints by building churches, creating icons or statues, performing vigils, and worshipping their relics; however, not the saint is worshipped, but God through the saint. Most Protestant denominations do not recognize saints.
Second coming of Jesus Christ: As promised in the New Testament, Christians expect JesusChrist to return to Earth at an unknown time to perform the final judgment of the living and dead and restore those willing to their natural state in eternal direct communication with God in Heaven. The second coming is a central dogma of Christian eschatology, preceded and followed by many apocalyptic events. The early Christians expected this event to happen before the Apostles died, while throughout the centuries, there were many attempts to predict a date. This belief is almost universal across denominations.
Septuagint: Latin for “seventy”, it refers to the “Translation of the Seventy,” and the Septuagint presents the earliest surviving Greek translation of the Old Testament devised by 72 Jewish scholars during the third century BCE. Initially intended for Greek-speaking Jews, this translation was adopted by Early Christians and churches and is still used today in some denominations. It includes books that are considered non-canonical by Rabbinic traditions and Protestant denominations.
Testament, New: A collection of up to 27 books (Gospels, Acts of the Apostles, Letters of Paul, Catholic Letters, Apocalypse) that describes the incarnation, life, death, and resurrection of Jesus Christ, the adventures of the Apostles while establishing new churches and, finally, the apocalypse. While these books were circulated among Christian communities since the first centuries of the Common Era, the full canon was finalized only in the fourth century. Churches in the Syriac tradition only recognize 22 books, and there are also various New Testament apocrypha, partially used by various traditions.
Testament, Old: The first part of the Christian Bible, in which God promises the coming of the Messiah. Based on the Jewish Scriptures, the Old Testament canon differs across denominations: for example, the Orthodox include all 49 books of the Septuagint, the Catholics recognize 46 books, while most Protestant traditions only accept 39. The Old Testament narrative includes the world's creation, the history of the Jews, stories about prophets, and versed works such as the Psalms.
Transubstantiation (or metousiosis): This term refers to the belief that, during the celebration of the Eucharist, the bread and wine are mystically transformed into the actual body and blood of Jesus Christ. While their outward appearance (taste, texture, and colour) remains the same, their essence is understood to have permanently changed. This transformation is not seen as a simple symbolic gesture but as a profound spiritual reality. It is believed by traditional churches (Assyrian, Catholic, Oriental Orthodox, Orthodox), albeit with different emphases (philosophical substance change vs transformation as an action of divine power).
Virgin Mary: The mother of Jesus Christ. According to the Gospels, she was a young Jewish girl from Nazareth named Mariam who, after consenting, carried and gave birth to Jesus Christ in human form. Since the Bible offers only limited information about her, most beliefs about her life come from apocryphal texts and local church traditions, so they vary significantly. The Virgin Mary is deeply cherished across Oriental Orthodox, Orthodox and Catholic traditions as the Mother of God and mediator for humankind to her Son. However, most Protestant denominations do not venerate her.
Vulgate: The Latin translation of the Bible, primarily devised by the Church Father Jerome in the fourth century CE. It became the standard Bible of the Catholic Church, officially affirmed by the Council of Trent (1545–1563). There were also successive editions, such as the Clementine Vulgate (the second edition of the Vulgate officially authorized by the Catholic Church in 1592) and the Nova Vulgata (the current official Latin translation). The Vulgate was the official version of the Bible across Europe, and it was only after the Reformation that translations into other languages became widespread.
World Council of Churches (WCC): Serving the cause of ecumenism, world councils have been organized among various churches since the beginning of the 20th century. In 1948, the World Council of Churches (WCC) was established, including most Orthodox churches, the Anglican church, and various Protestant denominations, from the West as well as in the Global South, counting 356 member churches today (according to their website). The WCC holds assemblies worldwide every eight years under various thematic umbrellas. The goal is to foster cross-denominational dialogue, aiming to bring the churches to communion. The Catholic Church is not a member of the WCC.