History & Origins
The Roman Catholic Church traces its origins to the ministry of Jesus of Nazareth in first-century Judea and, specifically, to his declaration to the apostle Simon Peter: "You are Peter, and on this rock I will build my Church." From that commission, Catholics understand a continuous, unbroken line of authority descending through 266 popes across two thousand years of history.
The early Christian community in Rome — where both Peter and Paul were martyred, probably under the Emperor Nero around 64–68 CE — occupied a position of special prestige within the wider church from the earliest centuries. The Bishop of Rome gradually claimed primacy among the five great patriarchates of the ancient church (Rome, Constantinople, Alexandria, Antioch, and Jerusalem), a claim resisted by the East but increasingly accepted in the Latin West. The Edict of Milan (313 CE), which legalized Christianity under Constantine, and the establishment of Christianity as the official religion of the Roman Empire under Theodosius I (380 CE) transformed the Church from a persecuted minority to the dominant institution of late antique and medieval civilization.
The fall of the Western Roman Empire (476 CE) left the papacy as the paramount moral and often political authority in Western Europe. The medieval papacy reached the height of its temporal power under Innocent III (1198–1216), who claimed the right to depose kings. This period also produced the great Gothic cathedrals, the Scholastic theological synthesis of Thomas Aquinas, the founding of the monastic orders, and the universities — all institutions that the Catholic Church initiated or nurtured. The Great Schism of 1054 permanently divided Western Catholicism from Eastern Orthodoxy over questions of papal authority and theological method.
"You are Peter, and on this rock I will build my Church, and the gates of Hades will not overcome it. I will give you the keys of the kingdom of heaven."
Matthew 16:18–19 — The scriptural foundation of the Catholic doctrine of the papacyThe Protestant Reformation (1517 onward) shattered Western Christianity's institutional unity, stripping the papacy of authority over large portions of Northern Europe and triggering a century of religious warfare. The Catholic response — the Counter-Reformation — was launched at the Council of Trent (1545–1563), which clarified Catholic doctrine against Protestant challenges, reformed clerical discipline, and launched a global missionary enterprise through new orders like the Society of Jesus (Jesuits). The 16th and 17th centuries saw Catholic missionaries evangelize the Americas, sub-Saharan Africa, India, China, and Japan, establishing the worldwide character of the Catholic Church that defines it today.
The First Vatican Council (1869–70) defined the doctrine of papal infallibility amid the political upheavals that stripped the papacy of its temporal territories. The Second Vatican Council (1962–65) — convened by Pope John XXIII and continued by Paul VI — undertook the most sweeping renewal of Catholic life since Trent: reforming the liturgy (Mass celebrated in vernacular languages rather than Latin), affirming religious liberty, initiating ecumenical dialogue with other Christians and with Judaism, and articulating a vision of the Church as the "People of God" rather than primarily a hierarchical institution. Vatican II's legacy remains the defining debate of contemporary Catholicism.
Theology & Doctrine
Catholic theology is among the most developed and internally consistent intellectual traditions in human history, integrating scripture, apostolic tradition, philosophical reason, and the authoritative teaching of the Magisterium into a comprehensive account of God, humanity, the Church, and salvation.
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IThe Magisterium — The Living Teaching Authority
Catholic doctrine holds that Jesus entrusted the deposit of faith not only to a written text but to a living community — the Church — which continues to interpret and apply that deposit under the guidance of the Holy Spirit. The Magisterium is the Church's authoritative teaching office, exercised by the Pope and bishops in communion with him. Papal infallibility — defined at Vatican I (1870) — holds that when the Pope speaks ex cathedra on matters of faith and morals for the whole Church, he is preserved from error. This has been formally invoked only twice: the Immaculate Conception (1854) and the Assumption of Mary (1950). The Magisterium is not above scripture or tradition but is their authoritative interpreter.
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IIScripture and Sacred Tradition
Catholic theology holds that divine revelation comes through two interrelated channels: Sacred Scripture (the 73-book Catholic Bible, including the deuterocanonical books accepted at Trent) and Sacred Tradition — the living transmission of the apostolic faith through the Church's liturgy, creedal formulations, the writings of the Church Fathers, and the continuous practice of the Christian community. Scripture and Tradition are not two separate sources but one stream of the Word of God, interpreted together under the Magisterium. This distinguishes Catholic epistemology from the Protestant sola scriptura principle, which rejects Tradition as a co-equal source of binding authority.
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IIIJustification, Grace, and Merit
Catholic soteriology affirms that salvation is entirely the work of God's grace, but understands grace as genuinely transforming the believer — not merely covering sin (as in the Lutheran imputation model) but making the person actually righteous (infused righteousness). Justification begins at baptism and is a lifelong process of growth in holiness (sanctification). Catholic theology holds that works performed in a state of grace genuinely merit eternal life — not because human effort earns salvation, but because God has freely chosen to honor the acts of grace-enabled love with a share in his own life. This was the central soteriological dispute of the Reformation. The 1999 Joint Declaration on the Doctrine of Justification with the Lutheran World Federation marked a historic convergence on key points, while acknowledging remaining differences.
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IVThe Real Presence — Eucharistic Theology
The doctrine of transubstantiation holds that at the words of consecration during Mass, the substance of the bread and wine is wholly converted into the Body and Blood of Jesus Christ — while the accidents (appearance, taste, feel) of bread and wine remain. The consecrated host is therefore not a symbol of Christ but Christ himself — truly present, whole and entire, under each eucharistic species. This doctrine, defined at the Fourth Lateran Council (1215) and reaffirmed at Trent, makes the Mass the central act of Catholic worship: the re-presentation (not repetition) of the sacrifice of Calvary, making the saving event of the cross present in every time and place where Mass is celebrated.
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VMariology — The Role of the Virgin Mary
Catholic Mariology occupies a distinctive and often disputed place in Christian theology. The dogmas of the Immaculate Conception (Mary conceived without original sin, defined 1854) and the Assumption (Mary taken body and soul into heaven at the end of her earthly life, defined 1950) express the Church's conviction that Mary's unique role as Mother of God (Theotokos — "God-bearer," defined at Ephesus, 431 CE) required a unique participation in the grace of her Son. Mary is venerated (hyperdulia) above all the saints but worshipped (latria) only by those who misunderstand Catholic teaching — worship belongs to God alone. Catholic devotion to Mary includes the Rosary, Marian feast days, apparition sites (Lourdes, Fatima), and prayers of intercession.
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VIPurgatory and the Communion of Saints
Catholic doctrine holds that those who die in God's grace but still imperfectly purified undergo a final purification — purgatory — before entering the full joy of heaven. This is not a second chance after death but the completion of the sanctification that began in baptism. The doctrine grounds the Catholic practice of praying for the dead and the offering of Masses for the repose of souls. Closely related is the communion of saints — the belief that the Church comprises not only the living faithful on earth (the Church Militant) but the souls being purified in purgatory (the Church Suffering) and the saints in heaven (the Church Triumphant), all in living communion with one another and with Christ the Head.
Sacred Texts & Tradition
Catholic Christianity draws on a broader canon of scripture than Protestant traditions, alongside a rich body of tradition, conciliar definitions, and magisterial teaching that together constitute the full deposit of faith.
The Catholic biblical canon includes 73 books: the 27 books of the New Testament common to all Christians, and 46 Old Testament books — including seven deuterocanonical books (Tobit, Judith, 1–2 Maccabees, Wisdom, Sirach/Ecclesiasticus, and Baruch) absent from the Protestant Old Testament, which follows the 39-book Hebrew canon. The deuterocanonical books were accepted by the Council of Trent (1546) as canonical on the basis of their inclusion in the Septuagint — the Greek translation used by the earliest Christians. The New American Bible Revised Edition (NABRE) and the Jerusalem Bible are widely used in Catholic liturgy and scholarship.
The writings of the Church Fathers — the theologians of the first eight centuries whose work shaped Catholic doctrine — constitute a primary source of Sacred Tradition. Major figures include Ignatius of Antioch, Irenaeus of Lyon, Tertullian, Origen, Athanasius, Basil the Great, Gregory of Nazianzus, Gregory of Nyssa, Ambrose of Milan, Jerome (translator of the Latin Vulgate Bible), Augustine of Hippo, John Chrysostom, Cyril of Alexandria, and Pope Gregory the Great. Their exegesis, dogmatic works, homilies, and letters are authoritative witnesses to apostolic faith and continue to be studied in Catholic seminaries and theological faculties worldwide.
The Catholic Church recognizes 21 Ecumenical Councils as its highest doctrinal authorities after the Pope: Nicaea I (325), Constantinople I (381), Ephesus (431), Chalcedon (451), Constantinople II (553), Constantinople III (680–681), Nicaea II (787), plus nine medieval councils, and Vatican I (1869–70) and Vatican II (1962–65). The councils defined the doctrines of the Trinity, the Incarnation, the canon of scripture, transubstantiation, justification, papal infallibility, and the Church's engagement with the modern world. Their decrees are binding on all Catholics.
Commissioned by the Extraordinary Synod of Bishops (1985) and published by Pope John Paul II in 1992, the Catechism of the Catholic Church is the comprehensive reference text for Catholic doctrine — the first universal catechism since the Roman Catechism of the Council of Trent (1566). Organized around the Creed, the Sacraments, the Commandments, and the Lord's Prayer, it synthesizes scripture, tradition, and magisterial teaching in accessible form. Translated into dozens of languages, it remains the authoritative summary of what the Catholic Church believes, celebrates, lives, and prays, and is the standard reference for catechesis, RCIA (Rite of Christian Initiation of Adults), and theological education worldwide.
Architects of Catholic Thought
The Catholic intellectual and spiritual tradition has produced an extraordinary range of theologians, mystics, missionaries, and reformers across twenty centuries. These figures represent the tradition's most enduring voices.
The most influential theologian in the history of Western Christianity. Augustine's Confessions — a spiritual autobiography addressed to God — and The City of God shaped Western thought on grace, original sin, predestination, free will, and the relationship between the Church and political order. His anti-Pelagian writings, insisting on the absolute priority of divine grace against any notion that human beings can merit salvation by their own effort, defined the terms of Western soteriology from the 5th century through the Reformation and beyond. No single thinker has shaped Catholic (and, ironically, Protestant) theology more deeply.
The Dominican friar who produced the Summa Theologiae — the greatest systematic theology in the Catholic tradition and one of the most ambitious intellectual works in history. Aquinas synthesized the philosophy of Aristotle with Christian theology, producing the Scholastic tradition that remains the intellectual backbone of Catholic education. His Five Ways — arguments for the existence of God — remain the most studied natural theology in Western philosophy. Pope Leo XIII's encyclical Aeterni Patris (1879) declared Thomism the normative philosophical method for Catholic thought, a status reaffirmed by Vatican II. Aquinas was canonized in 1323 and declared a Doctor of the Church.
The first woman declared a Doctor of the Church (1970), Teresa of Ávila was a Spanish Carmelite mystic, reformer, and writer whose Interior Castle and The Way of Perfection remain the most widely read works on Catholic contemplative prayer. Experiencing visions and mystical union with God from her forties onward, Teresa undertook the radical reform of the Carmelite order — establishing the Discalced Carmelites with her collaborator John of the Cross — against significant institutional resistance. Her account of the soul's journey through seven "mansions" toward union with God is the definitive Catholic map of the mystical life.
A Basque nobleman and soldier whose conversion experience during recovery from a battle wound led him to found the Society of Jesus (Jesuits) in 1540 — the most influential Catholic religious order of the modern era. The Jesuits became the shock troops of the Counter-Reformation: establishing colleges and universities across Europe (over 700 remain active today, including Georgetown and Fordham), sending missionaries to India, China, Japan, and the Americas, and serving as papal advisors and theologians at the Council of Trent. Ignatius's Spiritual Exercises — a structured 30-day retreat — remains one of the most widely practiced Christian methods of prayer and discernment. Pope Francis is the first Jesuit pope.
Born Anjezë Gonxhe Bojaxhiu in Skopje to Albanian parents, Teresa joined the Sisters of Loreto and was sent to India, where a "call within a call" in 1946 led her to leave the convent and serve the poorest of the poor in the slums of Calcutta. She founded the Missionaries of Charity (1950), which now operates in 139 countries, serving the sick, dying, orphaned, and destitute. Awarded the Nobel Peace Prize in 1979, she was beatified by Pope John Paul II in 2003 and canonized by Pope Francis in 2016. Her posthumously published letters revealed decades of spiritual darkness — a "dark night of the soul" — alongside her public ministry, making her a powerful symbol of perseverance in faith.
Karol Józef Wojtyła — the first non-Italian pope since 1523 — transformed the modern papacy through a 26-year pontificate defined by global travel (129 countries), philosophical depth (his Theology of the Body redefined Catholic sexual ethics), political courage (his support for Solidarity in Poland contributed to the fall of Communism in Eastern Europe), and personal holiness that survived an assassination attempt in 1981 with public forgiveness of his would-be assassin. He canonized more saints (482) than all his predecessors combined, initiated World Youth Day, and was himself beatified in 2011 and canonized in 2014 — the fastest canonization in modern Catholic history.
Practices & The Seven Sacraments
Catholic sacramental life is the structured, liturgical encounter between the believer and the saving grace of Christ, mediated through the Church's ordained ministry and enacted through physical signs. The seven sacraments mark and sanctify every major threshold of human life.
The foundational sacrament of Christian life — entry into the Body of Christ through water in the name of the Trinity, effecting the forgiveness of original and personal sin, regeneration of the soul, and incorporation into the Church. Catholic theology holds that baptism is necessary for salvation (John 3:5), though "baptism of desire" applies to those who sincerely seek God but die before receiving the sacrament. Infant baptism has been the normative Catholic practice since at least the 2nd century.
The sacrament in which the baptized Christian receives the fullness of the Holy Spirit — typically administered by a bishop through anointing with chrism (consecrated oil) and the laying on of hands. Confirmation completes baptismal grace, strengthening the recipient for active witness to the faith, and is the final sacrament of initiation alongside Baptism and the Eucharist. In the Latin Rite it is typically conferred in adolescence; in the Eastern Catholic Rites, immediately after baptism as in Orthodoxy.
The central act of Catholic worship and "the source and summit of the Christian life" (Lumen Gentium). At Mass, the priest acting in persona Christi (in the person of Christ) repeats the words of the Last Supper, and the doctrine of transubstantiation holds that the bread and wine become the Body and Blood of Christ. Catholics in a state of grace are obliged to receive Communion at least once a year (Easter duty) and are encouraged to receive at every Mass. The Sunday Mass obligation reflects the centrality of the Eucharist to Catholic identity.
The sacrament through which mortal sins committed after baptism are forgiven through the absolution of a priest acting with the authority given by Christ to the apostles (John 20:23). The penitent confesses sins to a priest, expresses contrition, receives absolution, and performs a penance assigned by the confessor. Regular confession — at least once a year for Catholics conscious of mortal sin — is a discipline that Catholic spiritual direction consistently commends as essential to ongoing conversion and growth in holiness.
The sacrament administered to those seriously ill or in danger of death, through anointing with oil and the laying on of hands by a priest, conferring spiritual strengthening, forgiveness of sins, and sometimes physical healing. Formerly called "Extreme Unction" and associated primarily with the dying, Vatican II restored its application to all who are seriously ill — not only those at the point of death. When combined with Confession and the Eucharist (viaticum — "food for the journey"), it constitutes the Last Rites for the dying.
The most widely practiced Catholic private devotion — a structured meditation on twenty mysteries of the life of Christ, grouped into four sets (Joyful, Luminous, Sorrowful, Glorious), using a string of beads to count repetitions of the Hail Mary, Our Father, and Glory Be. Rooted in medieval monastic practice and developed through the 13th–16th centuries (traditionally associated with St. Dominic), the Rosary was championed by successive popes as the quintessential Catholic prayer form. Marian apparitions at Lourdes (1858) and Fatima (1917) are associated with requests for its wider practice.
The sacrament by which men are ordained as deacons, priests, or bishops — configured to Christ the Head and Shepherd — to serve the People of God through word, sacrament, and governance. Catholic teaching holds that ordination confers a permanent, indelible character on the soul. The requirement of celibacy for Latin Rite priests (not universal in Eastern Catholic Rites or for permanent deacons) is a disciplinary rather than dogmatic requirement, though celibacy as a sign of total self-giving to God and the Church is deeply embedded in Catholic tradition.
Catholic teaching holds that marriage between the baptized is a sacrament — a covenant, not merely a contract, reflecting the unbreakable union of Christ and the Church (Ephesians 5). The sacrament is administered by the spouses themselves in their consent before a priest and witnesses. A sacramental marriage is held to be indissoluble — "what God has joined together, let no one separate." Civil divorce does not dissolve a sacramental marriage in Catholic teaching; an annulment (a declaration that a valid sacramental marriage never existed) is required before remarriage. The Church's theology of marriage as a life-giving, permanent, faithful union grounds its teaching on contraception (Humanae Vitae, 1968) and sexual ethics.
Rites within the Catholic Church
The Catholic Church is not a single-rite institution but a communion of 24 particular churches (one Latin and 23 Eastern), all in full communion with the Pope, each with its own liturgical tradition, canon law, and theological emphasis.
The largest rite of the Catholic Church, following the Roman Liturgical tradition as reformed by the Second Vatican Council. The Ordinary Form of the Mass (the "Novus Ordo," promulgated 1969) is celebrated in vernacular languages worldwide. The Extraordinary Form (the Tridentine Mass, codified 1570) was liberalized by Pope Benedict XVI's Summorum Pontificum (2007) and subsequently restricted by Pope Francis's Traditionis Custodes (2021). The Latin Rite encompasses the overwhelming majority of Catholics in the Americas, Western Europe, and sub-Saharan Africa.
A family of Eastern Catholic churches following the Byzantine liturgical tradition — the same rite used by the Eastern Orthodox churches — while remaining in full communion with Rome. The largest is the Ukrainian Greek Catholic Church (~5 million). Others include the Melkite Greek Catholic Church, Romanian Greek Catholic Church, Ruthenian Catholic Church, and Greek Byzantine Catholic Church. Byzantine Catholics use the Divine Liturgy of St. John Chrysostom or St. Basil the Great, celebrate the sacraments as in Orthodoxy (including immediate Communion for infants), and may have married priests. Their existence reflects centuries of reunion movements between Eastern Christians and Rome.
An ancient Syriac-tradition Eastern Catholic church based in Lebanon, tracing its origins to the 5th-century hermit Maron and his followers, who maintained communion with Rome through the Crusader period and formally united with the papacy in the 12th century. The Maronite Church has never been in schism from Rome and uses the West Syriac (Antiochene) liturgical tradition, celebrated primarily in Syriac and Arabic. Lebanon — where Maronites have historically constituted a significant portion of the population — has a Maronite Patriarch and a political system that reserves the presidency for Maronite Christians. The largest Maronite communities outside Lebanon are in Brazil, the United States, and Australia.
An Eastern Catholic church of the East Syriac liturgical tradition based historically in Iraq and Iran, in communion with Rome since 1552. The Chaldean Church uses the ancient Aramaic liturgical tradition closely related to that of the Assyrian Church of the East (which is not in communion with Rome). The Chaldean Catholic Patriarch is based in Baghdad. The Christian population of Iraq — historically centered on the Chaldean Church — has been severely reduced by violence and emigration since 2003; the diaspora in the United States, Australia, and Western Europe now rivals the population remaining in Iraq.
The Syro-Malabar Church traces its origins to the evangelization of India by the apostle Thomas in the 1st century — one of the oldest Christian communities in the world. It follows the East Syriac (Chaldean) liturgical tradition and has been in communion with Rome since the Portuguese arrived in Kerala in the 16th century. The Syro-Malankara Catholic Church, smaller and following the West Syriac tradition, was founded in 1930 by the former Metropolitan Mar Ivanios, who led a group of Orthodox Christians into full communion with Rome. Both churches retain their ancient liturgical heritage while maintaining full union with the papacy.
The Communion of Saints
Catholic hagiography — the study and veneration of the saints — encompasses more than ten thousand canonized men and women across twenty centuries, from the early martyrs of the Roman persecutions to holy men and women of the 20th century. The saints are not worshipped but venerated as intercessors and exemplars — witnesses that a fully human life can be lived in union with God.
The formal process of canonization — investigation of the candidate's virtuous life and heroic virtue, verification of miracles attributed to their intercession, beatification, and finally canonization — was systematized in the 12th century and reformed most recently by Pope John Paul II in 1983. Before formal canonization, sainthood was often declared by popular acclaim or episcopal recognition. The Church's canon of saints is the most diverse gallery of human holiness in any religious tradition: theologians and illiterates, rulers and servants, martyrs and contemplatives, missionaries and mystics, spanning every continent, culture, and era.
The Successors of Peter
The papacy is the most ancient continuous office in the Western world. From Peter's ministry in Rome to Francis today, 266 men have served as Bishop of Rome — an unbroken line stretching across two thousand years of history, schism, reform, and renewal.
The papal office has encompassed men of extraordinary sanctity and devastating moral failure, scholar-popes and warrior-popes, reformers and reactionaries, martyrs and political survivors. The full list — from Peter through the medieval antipopes, the Avignon papacy, the Renaissance, the Counter-Reformation, and the modern era — is one of the most consequential biographical registers in Western history.
Glossary of Catholic Terms
A reference guide to the essential vocabulary of Roman Catholic theology, liturgy, and institutional life.
The Catholic doctrine that at the words of consecration during Mass, the entire substance of the bread and wine is converted into the Body and Blood of Christ, while the accidents (sensible appearances) of bread and wine remain. Defined by the Fourth Lateran Council (1215) and reaffirmed at Trent (1551). The consecrated host is therefore the Real Presence of Christ — not a symbol — and is adored in Eucharistic devotion, exposed in monstrance for Benediction, and reserved in the tabernacle for adoration and communion of the sick.
The Church's living teaching authority — the office of authentic interpretation of the Word of God entrusted to the Pope and bishops in communion with him. The Magisterium is "ordinary" (the regular, ongoing teaching of bishops in communion with Rome) or "extraordinary" (solemn dogmatic definitions by ecumenical councils or papal ex cathedra pronouncements). Papal infallibility applies only to the extraordinary Magisterium in its most solemn form. The Magisterium does not create new revelation but guards and interprets the deposit of faith entrusted to the Church by the apostles.
The Catholic and Orthodox doctrine that the authority conferred on the apostles by Christ is transmitted through a continuous, unbroken chain of ordination by the laying on of hands from bishop to bishop, from the apostolic age to the present. This succession guarantees the validity of sacraments and the authentic transmission of apostolic teaching. The Catholic Church does not recognize the validity of Protestant orders, holding that the Anglican and Protestant reformations broke apostolic succession. The validity of Eastern Orthodox orders is affirmed.
The remission before God of the temporal punishment due to sins already forgiven as to guilt — granted by the Church through the merits of Christ and the saints (the "treasury of merit"). A plenary indulgence remits all temporal punishment; a partial indulgence remits some. Indulgences require specific conditions (sacramental confession, Eucharistic Communion, prayer for the Pope's intentions, and freedom from attachment to sin). The abuse of indulgences — their sale — was the immediate trigger of Luther's Ninety-Five Theses (1517) and one of the primary causes of the Reformation. The Council of Trent abolished the sale of indulgences while affirming the doctrine itself.
A formal papal letter addressed to bishops (and increasingly to all the faithful) on a significant matter of doctrine, morality, or social concern. Encyclicals are the most authoritative form of ordinary Magisterium, though not infallible definitions. Landmark encyclicals include Leo XIII's Rerum Novarum (1891, founding Catholic Social Teaching), Pius XII's Mystici Corporis (1943, on the Church as the Body of Christ), Paul VI's Humanae Vitae (1968, on conjugal love and contraception), John Paul II's Veritatis Splendor (1993, on moral theology), and Francis's Laudato Si' (2015, on care for creation).
The system of laws governing the Catholic Church — the world's oldest continuously operative legal system, predating the emergence of most modern civil law systems. The current Code of Canon Law for the Latin Church (1983, revised from the 1917 Code) and the Code of Canons of the Eastern Churches (1990) regulate all aspects of Church life: the sacraments, governance, trials, penalties, and the rights and duties of the faithful. Canon Law is distinct from civil law and operates within the Church's own sphere of competence; its courts handle matters such as marriage annulments, clerical discipline, and ecclesiastical property.
The penultimate step in the Catholic canonization process, by which the Pope declares that a deceased person lived a life of heroic virtue and is among the blessed in heaven. Beatification permits public veneration of the Blessed in specific regions or religious communities but not yet in the universal Church. It typically requires verification of one miracle attributed to the candidate's intercession (martyrs may be beatified without a verified miracle). Beatification is followed by canonization — which requires a second verified miracle and declares the person a saint of the universal Church whose feast day is added to the Roman Calendar.
The secret assembly of cardinal-electors convened in the Sistine Chapel following the death or resignation of a pope to elect his successor. The conclave system was formalized by Pope Gregory X at the Second Council of Lyon (1274) in response to a vacancy that had lasted nearly three years. Cardinals under 80 are eligible to vote; a two-thirds majority is required for election. The famous signal of white smoke (fumata bianca) from the Sistine chimney signals the election of a new pope, followed by the announcement "Habemus Papam" ("We have a Pope") from the loggia of St. Peter's Basilica. The 2013 conclave that elected Francis concluded in just two days — one of the shortest in modern history.