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Oakeley, Frederick - English Tractarian and convert (1802-1880)
O Antiphons - Seven antiphons to the Magnificat, used in the Divine Office in the days preceding Christmas
Oates's Plot - A 'Popish Plot' which, during the reign of Charles II of England, Titus Oates pretended to have discovered.
Oaths - An invocation to God to witness the truth of a statement
Oaths, English Post-Reformation - The English Reformation having been imposed by the Crown, it was natural that submission to the essential points of its formularies should have been exacted with some solemnity, by oath, test, or formal declaration . . .
Oaxaca - Diocese and city in the southern part of Mexico
Obazine, Monastery of - Located in the Diocese of Tulle; founded by St. Stephen of Obazine about 1134.
Obba - Titular see in Byzacena, northern Africa of unknown history
Obedience - The complying with a command or precept.
Obedience, Religious - The general submission which religious vow to God, and voluntarily promise to their superiors, in order to be directed by them in the ways of perfection according to the purpose and constitutions of their order.
Obedientiaries - The lesser officials of a monastery who were appointed by will of the superior.
Oblate Sisters of Providence - A congregation of black nuns founded at Baltimore, Maryland
Oblates of Mary Immaculate - Religious society founded in 1816
Oblates of St. Francis de Sales - A congregation of priests founded originally by Saint Francis de Sales at the request of Saint Jane de Chantal.
Oblati, Oblatæ, Oblates - A word used to describe any persons, not professed monks or friars, who have been offered to God, or have dedicated themselves to His service, in holy religion.
Obligation - Defined in the 'Institutes' of Justinian as a 'legal bond which by a legal necessity binds us to do something according to the laws of our State'
O'Braein, Tighernach - Irish annalist and abbot (d. 1088)
Obregonians - Congregation of Franciscan men founded by Bernardino Obregon
Obreption - A type of fraud by which an ecclesiastical rescript is obtained
O'Brien, Terence Albert - Irish Dominican (1600-1651)
O'Bruadair, David - Irish poet (1625-1698)
Observatory, Vatican - Gregory XIII ordered a tower to be erected in a convenient part of the Vatican buildings, and to be fitted out with the greatest and best instruments of the time
O'Callaghan, Edmund Bailey - Physician, publicist, and historian (1797-1880)
O'Carolan, Torlogh - Called 'the last of the Irish bards' (1670-1737)
Occam, William of - Biographical article on the fourteenth-century Franciscan philosopher
Occasionalism - The metaphysical theory which maintains that finite things have no efficient causality of their own, but that whatever happens in the world is caused by God, creatures being merely the 'occasions' of the Divine activity.
Occasions of Sin - External circumstances — things or persons — which incite or entice one to sin.
Occleve, Thomas - English poet (1368-1450)
Occult Art, Occultism - An attempt to work apparent miracles not by the power of God, but by the use of hidden forces beyond man's control
Occurrence - The coinciding of two liturgical offices on one and the same day
Oceania, Vicariate Apostolic of Central - Vicariate in western Oceania
Ockham, William of - Biographical article on the fourteenth-century Franciscan philosopher
O'Connell, Daniel - Irish patriot (1775-1847)
O'Conor, Charles - The son of Irish immigrants, he was an eminent New York lawyer and orator. He defended Jefferson Davis and prosecuted Boss Tweed. Died 1884
O'Conor, Charles - Called 'the Venerable.' Eighteenth-century Irish antiquarian
Octave - A period of eight days, often observed liturgically
Octavarium Romanum - A liturgical book which may be considered as an appendix to the Roman Breviary
O'Cullenan, Gelasius - Cistercian Abbot of Boyle, Ireland (d. 1580)
O'Curry, Eugene - Irish scholar (1796-1862)
O'Daly, Daniel - Diplomat and historian (1595-1662)
O'Daly, Donogh Mór - Irish poet (d. 1244)
Odense, Ancient See of Odense - Former diocese located in Denmark
Odescalchi, Carlo - Cardinal, prince, archbishop, and Jesuit (1786-1841)
O Deus Ego Amo Te - The first line of two Latin lyrics sometimes attributed to St. Francis Xavier
O'Devany, Cornelius - Bishop of Down and Connor, Ireland (1532-1612)
Odilia, Saint - Patroness of Alsace, d. 720, founded the convent of Hohenburg
Odilo, Saint - Abbot of Cluny. He died in 1048
Odin, John Mary - Lazarist missionary and bishop (1801-1870)
Odington, Walter - English Benedictine (d. 1330)
Odo, Saint - Second abbot of Cluny, died 942
Odo, Saint - Benedictine monk, Archbishop of Canterbury, died in 959
O'Donnell, Edmund - The first Jesuit executed by the English government (1542-1575)
O'Donovan, John - Irish historian and antiquarian (1806-1861)
Odo of Cambrai, Blessed - Benedictine abbot, bishop of Cambrai, exiled for political reasons, d. 1113
Odo of Canterbury - Abbot of Battle (d. 1200)
Odo of Cheriton - Preacher and fabulist (d. 1247)
Odo of Glanfeuil - Abbot and ninth-century hagiographer
O'Dugan, John - Irish writer (d. 1372)
O'Dwyer, Joseph - American physician, inventor of intubation (1841-1898)
Œcolampadius, John - Protestant theologian and organizer of Protestantism at Basle (1482-1531)
Œconomus, Episcopal - An individual who is appointed to take charge of the temporal goods of a church or monastery
Œcumenius - Biblical commentator (c. 990)
Oertel, John James Maximilian - Bavarian journalist (1811-1882)
Oettingen - Abbey in Bavaria
Offa - King of Mercia (d. 796)
Offerings - Covers the Jewish and Christian practices of offerings and tithes
Offertory - The rite by which the bread and wine are presented to God before they are consecrated
Office, Divine - Brief essay on the historical development of the Liturgy of the Hours
Office of the Dead - Historical article on a special set of prayers for the deceased
O'Fihely, Maurice - Archbishop of Tuam (1460-1513)
O Filii et Filiæ - The first line of a hymn celebrating the mystery of Easter.
Ogdensburg, Diocese of - Diocese in upstate New York
Oggione, Marco D' - Milanese painter (1470-1549)
Ogilvie, John, Venerable - Scotsman, raised Calvinist, converted to Catholicism, became a Jesuit priest and missionary to his native land, was tortured and martyred in 1615
Ogliastra - Diocese in Sardinia, Italy
O'Growney, Eugene - Irish-American priest, patriot, and scholar (1863-1899)
O'Hagan, John - Irish lawyer and man of letters (1822-1890)
O'Hagan, Thomas - First Baron of Tullyhogue (1812-1885)
O'Hanlon, John - Irish-American priest (1821-1905)
O'Hara, Theodore - American writer (1822-1867)
O'Hely, Patrick - Bishop of Mayo, Ireland (d. 1579)
O'Herlahy, Thomas - Bishop of Ross, Ireland (d. 1579)
O'Higgins, Ambrose and Bernard - South American patriots of Irish background
Ohio - The seventeenth state of the American Union
Ohler, Aloys Karl - German educationist (1817-1889)
O'Hurley, Dermond - Archbishop of Cashel, Ireland (d. 1584)
O'Hussey, Maelbrighte - Franciscan friar (d. 1614)
Oil of Saints - An oily substance which flows from the relics or burial places of certain saints
Oils, Holy - Oil is a product of great utility the symbolic signification of which harmonizes with its natural uses. It serves to sweeten, to strengthen, to render supple; and the Church employs it for these purposes in its rites
Ointment in Scripture - That the use of oily, fragrant materials to anoint the body is a custom going back to remote antiquity is evidenced by the Old Testament as well as other early literatures. . .
Ojeda, Alonso de - Spanish explorer (1466-1508)
Okeghem, Jean d' - Contrapuntist, founder and head of the second Netherland school (1430-1495)
Oklahoma - The forty-sixth state of the Union
Olaf Haraldson, Saint - Martyr and King of Norway, d. 1030
Oláh, Nicolaus - Hungarian archbishop (1493-1568)
Olba - Titular see in Isauria, suffragan of Seleucia.
Old Catholics - The sect organised in German-speaking countries to combat the dogma of Papal Infallibility.
Old Chapter, The - The origin of the body, fomerly known as the Old Chapter, dates from 1623 . . .
Oldcorne, Ven. Edward - Englishman, Jesuit priest, martyred in 1606. Biography
Oldenburg - A grand duchy, one of the twenty-six federated states of the German Empire.
Old Hall (St. Edmund's College) - Founded in 1793 in Hertfordshire, England
Oldham, Hugh - Bishop of Exeter (d. 1519)
Oldoini, Augustino - Historian and bibliographer (1612-1683)
Old Testament - The Apostle St. Paul declares himself (II Cor., iii, 6) a minister 'of the new testament', and calls (iii, 14) the covenant entered into on Mount Sinai 'the old testament'
Old Testament, Canon of the - Signifies the authoritative list or closed number of the writings composed under Divine inspiration, and destined for the well-being of the Church
O'Leary, Arthur - Irish Franciscan, preacher, polemical writer (1729-1802)
Olenus - Titular see and suffragan of Patras, in Achaia Quarta
Olesnicki, Zbigniew - Polish cardinal and statesman (1389-1455)
Olier, Jean-Jacques - Founder of the seminary and Society of St-Sulpice (1608-1657)
Olinda - Diocese in Brazil
Oliva - Suppressed Cistercian abbey near Danzig, founded sometime between 1170-78.
Oliva, Gian Paolo - Genoese Jesuit (1600-1681)
Olivaint, Pierre - French convert (b. 1816)
Oliver, George - English priest (1781-1861)
Olivet, Mount - A hill immediately east of Jerusalem
Olivetans - A branch of the white monks of the Benedictine Order, founded in 1319.
Olivi, Pierre Jean - Spiritual Franciscan and theological author (1248-1298)
Olivier de la Marche - Belgian chronicler and poet (1426-1501)
Ollé-Laprune, Léon - French Catholic philosopher (1839-1898)
Olmütz - Archdiocese in Moravia
O'Loghlen, Michael - Irish jurist (1789-1846)
Olympias, Saint - Widow, deaconess, renowned for her almsgiving, and a staunch supporter of St. John Chrysostom
Olympus - Titular see of Lycia in Asia Minor.
Omaha - Diocese in Nebraska, United States
Ombus - Titular see and suffragan of Ptolemais in Thebais Secunda.
O'Meara, Kathleen - Irish novelist and biographer (1839-1888)
Omer, Saint - Swiss-born bishop of Terouenne in Belgic Gaul, founder of a monastery. He died in about 670
Omission - The failure to do something one can and ought to do
Omnipotence - The power of God to effect whatever is not intrinsically impossible
O'Neill, Hugh - Earl of Tyrone (1550-1616)
O'Neill, Owen Roe - Soldier (1582-1649)
Onias - Name of several Jewish high priests who lived two and three centuries before Christ
Ontario - A province in Canada
Ontologism - An ideology which maintains that God and divine ideas are the first object of our intelligence and the intuition of God the first act of our individual knowledge
Ontology - An article on 'the science of being'
Oostacker, Shrine of - Miraculous shrine of the Blessed Virgin in Belgium
Opening Prayer (in the Mass) - The name now used only for short prayers before the Epistle in the Mass, which occur again at Lauds, Terce, Sext, None, and Vespers
Ophir - A people and a country mentioned in the Bible
Oporto - Diocese in Portugal
Oppenordt, Gilles-Marie - French rococo artist (1672-1742)
Oppido Mamertina - Diocese of Oppido Mamertina in Reggio Calabria, Italy
Optatus, Saint - Fairly long essay on the life and writings of this bishop, who argued against the Donatists. He died in about 387
Optimism - A metaphysical theory or an emotional disposition.
Option, Right of - In canon law, a way of obtaining a benefice or a title, by the choice of the new titulary himself.
O'Queely, Malachias - Archbishop of Tuam, Ireland (d. 1645)
Oracle - A Divine communication given at a special place through specially appointed persons; also the place itself.
Oran - Diocese in Algeria
Orange, Councils of - Two councils that were held in southern France
Orange Free State - One of the four provinces of the Union of South Africa
Orange River - Vicariate apostolic in South Africa
Orans - An iconographic type, commonly found in the Roman catacombs, of a female figure praying with extended arms
Orate Fratres - The exhortation addressed by the celebrant to the people before the Secrets in the Roman Mass
Oratorio - A musical composition for solo voices, chorus, orchestra, and organ, to a religious text generally taken from Holy Scripture.
Oratory - A structure other than a parish church, set aside by Church authority for prayer and the celebration of Mass
Oratory of Saint Philip Neri, The - Italian, Spanish, English, and other communities, which follow the rule of St. Philip Neri.
Oratory, French Congregation of the - Congregation founded in Paris at the beginning of the seventeenth century by Cardinal Pierre de Berulle
Orbellis, Nicolas d' - Franciscan theologian and philosopher and Scotist (1400-1475)
Orcagna - Florentine poet, artist and architect (d. 1368)
Orcistus - Titular see in Galatia Secunda.
Ordeals - A means of obtaining evidence by trials, through which the guilt or innocence of an accused person was supposedly established
Ordericus Vitalis - Norman historian (1075-1143)
Orders, Holy - The sacrament by which grace and spiritual power for the discharge of ecclesiastical offices are conferred.
Orders, The Military - A historical review of dozens of military orders
Ordinariate - This term is used in speaking collectively of all the various organs through which an ordinary, and especially a bishop, exercises the different forms of his authority.
Ordinary - Denotes any person possessing or exercising ordinary jurisdiction
Ordines Romani - The brief conspectus of the daily Office and Mass as adapted to the local calendar
Oregon - One of the Pacific Coast States
Oregon City - Former archdiocese in Oregon, United States
O'Reilly, Bernard - Irish-American historian (1820-1907)
O'Reilly, Edmund - Archbishop of Armagh (1616-1669)
O'Reilly, Edmund - English theologian (1811-1878)
O'Reilly, Hugh - Archbishop of Armagh (b. 1580)
O'Reilly, John Boyle - Poet, novelist, and editor (1844-1890)
O'Reilly, Myles William Patrick - Irish soldier, publicist, litterateur (1825-1880)
Oremus - Invitation to pray, said before collects and other short prayers and occurring continually in the Roman Rite.
Orense - Diocese and suffragan of Compostela in Spain
Oresme, Nicole - Article by Pierre Duhem on this medieval scientific thinker
Organ - A musical instrument which consists of one or several sets of pipes, each pipe giving only one tone, and which is blown and played by mechanical means.
Organic Articles, The - A name given to a law regulating public worship, comprising 77 articles relative to Catholicism, and 44 relative to Protestantism, presented by order of Napoleon to the Tribunate and the legislative body at the same time that he made these two bodies vote on the Concordat itself
Oria - Diocese near Brindisi in Italy
Oriani, Barnaba - Italian Barnabite and astronomer (1752-1832)
Oriental Study and Research - Comprises the scientific investigation and discussion of all topics — linguistics, archaeology, ethnology, etc. — connected with the East
Orientation of Churches - According to Tertullian the Christians of his time were, by some who concerned themselves with their form of worship, believed to votaries of the sun. . .
Orientius - Christian Latin poet of the fifth century.
Oriflamme - Legendary banner
Origen and Origenism - Provides a biography and review of his works, as well as commentary on posthumous influences and the Origenistic Crises
Original Sin - Original sin is (1) the sin that Adam committed; (2) a consequence of this first sin, the hereditary stain with which we are born on account of our origin or descent from Adam.
Orihuela - Diocese in Spain
Oriol, Saint Joseph - Earned a doctorate in theology, served as a parish priest, renowned for gifts of prophecy and miracles. St. Joseph died in 1702
Oristano - Diocese in Sardinia, Italy
Orkneys - A group of islands lying to the north of Scotland
Orlandini, Niccolò - Italian Jesuit (1554-1606)
Orléans - Diocese in France, suffragan of Paris
Orléans, Councils of - Six national councils held in the Merovingian period.
Orley, Barent Van - Belgian painter (1491-1542)
Orme, Philibert de l' - French architect (1512-1570)
Oropus - Titular see, suffragan of Anazarbus in Cilicia Secunda.
O'Rorke, Patrick Henry - Irish-American soldier, killed at Gettysburg (1837-1863)
Orosius, Paulus - Historian and Christian apologist (b. c. 380)
Orphans and Orphanages - The death of one or both parents makes the child of the very poor a ward of the community. . .
Orsi, Giuseppe Agostino - Florentine cardinal, theologian, and church historian (1692-1761)
Orsini - One of the most ancient and distinguished families of the Roman nobility, whose members often played an important role in the history of Italy
Orsisius - Egyptian monk of the fourth century
Ortelius, Abraham - Belgian cartographer, geographer and archeologist (1527-1598)
Orthodox Church - The body of Christians in union with the Patriarch of Constantinople but in schism with the Pope of Rome.
Orthodoxy - Right belief or purity of faith.
Orthodoxy, Feast of - Eastern feast that commemorates the restoration of the holy icons to the churches in 842
Orthosias - Titular see of Phoenicia Prima, suffragan of Tyre.
Ortolano Ferrarese - Painter of the Ferrara School (1490-1525)
Orval - Former Cistercian abbey in Luxemburg
Orvieto - Diocese in central Italy
Ory, Matthieu - French inquisitor and theologian (1492-1557)
Osaka - Large city in Japan
O Salutaris Hostia - Hymn used for the Benediction of the Most Blessed Sacrament
Osbald - King of Northumbria (d. 799)
Osbaldeston, Edward, Venerable - Profile of the English priest and martyr, who was executed at York in 1594
Osbern - English hagiographer (d. c. 1090)
Oscott (St. Mary's College) - Founded in England in 1793
Osee - The prophet and his book
Osimo - Diocese in Ascoli Piceno, Italy
Oslo, Ancient See of - Former diocese located in Norway
Osma - Diocese in Spain
Osmund, Saint - A Norman by birth, Osmund became bishop of Salisbury, and died in 1099
Osnabrück - Diocese in Germany, directly subject to the Holy See
Ossat, Arnaud d' - French cardinal, diplomat, and writer (1537-1604)
Ossory, Diocese of - Diocese in Ireland
Ostensorium - A vessel designed for the exhibition of some object of piety
Ostia and Velletri - Suburbicarian diocese near Rome
Ostiensis - Benedictine chronicler (1045-1115)
Ostracine - Titular see and suffragan of Pelusium in Augustamnica prima.
Ostraka, Christian - Inscriptions on clay, wood, metal, and other hard materials.
Ostrogoths - One of the two chief tribes of the Goths
O'Sullivan Beare, Philip - Irish writer (1590-1660)
Oswald, Saint - Archbishop of York, d. 992 while washing the feet of the poor, as was his daily custom during Lent
Oswald, Saint - King of Northumbria and martyr, d. 642
Oswin, Saint - Biography of the king and martyr, who was murdered in 651
Otfried of Weissenburg - The oldest German poet known by name (9th century)
Othlo - Benedictine monk of Ratisbon (1013-1072)
Othmar, Saint - First abbot of St. Gall. He died in prison in 759
Otho, Marcus Salvius - Details on the reign of Roman Emperor
O'Toole, Saint Lawrence - Confessor, abbot, and the first Irish-born bishop of Dublin, d. 1180
Otranto - An archdiocese and city in Apulia, southern Italy
Ottawa, Archdiocese of - Archdiocese of Ottawa in Canada
Ottawa, University of - Conducted by the Oblates of Mary Immaculate; founded in 1848.
Otto, Saint - Swabian courtier, was named bishop of Bamberg in 1102, and founded over twenty monasteries
Otto I, the Great - Roman emperor and German king (912-973)
Otto II - King of the Germans and Emperor of Rome (955-983)
Otto III - German king and Roman emperor (980-1002)
Otto IV - German king and Roman emperor (1182-1218)
Ottobeuren - Benedictine abbey in Bavaria
Otto of Freising - Bishop and historian (1111-1158)
Otto of Passau - Franciscan theologian
Otto of St. Blasien - German chronicler (d. 1223)
Ouen, Saint - Seventh-century Archbishop of Rouen, founder of several monasteries, devoted to theological studies, friend of St. Eloi
Our Father, The - Although the Latin term oratio dominica is of early date, the phrase 'Lord's Prayer' does not seem to have been generally familiar in England before the Reformation. During the Middle Ages the 'Our Father' was always said in Latin, even by the uneducated. Hence it was then most commonly known as the Pater noster
Our Lady, Help of Christians, Feast of - The invocation 'Help of Christians' originated in the sixteenth century.
Our Lady of Charity of the Good Shepherd - The aim of this institute is to provide a shelter for girls and women of dissolute habits, who wish to do penance for their iniquities and to lead a truly christian life
Our Lady of Good Counsel, Feast of - Feast honoring a popular Marian devotion
Our Lady of the Fields, Brothers of - A Canadian congregation founded in 1902 in the Diocese of Quebec by Father Brousseau.
Our Lady of the Snow - Feast commemorating the dedication of the church of Santa Maria Maggiore in Rome
Our Lady of Perpetual Help - A famous Byzantine-style picture painted on wood, with a background of gold
Our Lady of Perpetual Succour - A famous Byzantine-style picture painted on wood, with a background of gold
Overbeck, Friedrich - Convert and religious painter (1789-1869)
Overberg, Bernhard Heinrich - German ecclesiastic and educator (1754-1826)
Overpopulation, Theories of - Down to the end of the eighteenth century, very little attention was given to the relation between increase of population and increase of subsistence. . .
Oviedo - Diocese in Spain
Owen, Saint - Seventh-century Archbishop of Rouen, founder of several monasteries, devoted to theological studies, friend of St. Eloi
Owen, Saint Nicholas - A Jesuit lay brother, skilled in building hiding places for priests. He died under torture in 1606
Oxenford, John - English dramatist, critic, translator, and song-writer (1812-1877)
Oxenham, Henry Nutcombe - English controversialist and poet (1829-1888)
Oxford - Oxford, one of the most ancient cities in England, grew up under the shadow of a convent, said to have been founded by St. Frideswide as early as the eighth century. . .
Oxford, University of - Famous institution in England
Oxford Movement, The - Lengthy historical article on the Tractarian Movement includes information on John Henry Newman, as well as on other leading lights of this nineteenth-century Anglo-Catholic campaign, such as John Keble and Hurrell Froude
Oxyrynchus - Titular archdiocese of Heptanomos in Egypt.
Ozanam, Antoine-Frédéric - Great grand-nephew of Jacques Ozanam (1813-1853)
Ozanam, Jacques - French mathematician (1640-1717)
Ozias - Name of six Israelites mentioned in the Bible