Religion & Belief in the 4th century

231 sourced entries, 300 CE to 399 CE, oldest first. Also see Religion & Belief across every century or everything else in the 4th century.

• 300Peter of Alexandria becomes Patriarch of Alexandria.source
• 300The Tetrarchs are probably made in Egypt. After 330 they are moved to Constantinople and in 1204 they are installed at the corner of the facade of the St Mark's Basilica, Venice (approximate date).source
• 300Approximate date of the Synod of Elvira in Elvira, Spain, which prohibits interaction with Jews, pagans, and heretics.source
• 300Possible date of the Codex Vaticanus Graecus 1209 and Codex Sinaiticus, manuscripts of the Bible written in Greek.source
• 300The Panchatantra, a Sanskrit collection of fables and fairy tales, is written in India.source
• 300The Kama Sutra, an Indian handbook on the art of sexual love, is probably produced around this time by the sage Vatsyayana.source
• 301King Tiridates III (the Great) proclaims Christianity as the official state religion, making Armenia the first nation to adopt Christianity as its official religion (traditional date). Construction of the original Etchmiadzin Cathedral by Gregory the Illuminator begins.source
• 302Gregory the Illuminator is consecrated as Patriarch of Armenia by Leontius of Caesarea.source
• 302Iamblichus of Chalcis writes a treatise on magic and the occult.source
• 303January 6 – Baptism of Tiridates III of Armenia.source
• 303March 4 – Adrian and Natalia of Nicomedia are martyred.source
• 303September 25 – On a voyage preaching the gospel, Saint Fermin of Pamplona is beheaded in Amiens (Modern day France).source
• 303Etchmiadzin Cathedral is completed by Gregory the Illuminator and Tiridates III, king of Armenia.source
• 305The Council of Illiberis decrees that priests must be celibate. Additionally, it condemns visiting the homes of Jews and prohibits Christian women from marrying Jews, unless they have converted.source
• 305Patron of Pozzuoli, Saint Proculus, and patron of Naples, Saint Januarius are thrown to wild beasts in Pozzuoli's Flavian Amphitheater, then beheaded at Solfatara.source
• 305Maximinus Daza persecutes the Christians of Egypt, many of whom take refuge in the desert. In time, this refuge leads to the monastic life. In these monasteries, Coptic writing develops, supporting the propagation of Christian texts.source
• 305Catherine makes a public confession of the Christian gospel at a sacrificial feast ordered by Maximinus Daza at Alexandria. A virgin of royal descent, she is tortured on a spiked wheel (later called the "Catherine Wheel") and beheaded; her remains are spirited to Mount Sinai.source
• 305In this or the following year, the Baths of Diocletian are dedicated; the thermae become the largest imperial baths in Rome.source
• 306Metrophanes becomes bishop of Byzantium.source
• 306The Patriarchate of Lisbon is established.source
• 306Christianity is established in Roman Britain. British bishops participate in the councils of Arles (314), Nicaea (325) and Arminum (349).source
• 306The Synod of Elvira concludes with the issue of various canons, including one declaring that killing through a magic spell is a sin and the work of the devil.source
• 308May 27 or June 26 – Pope Marcellus I succeeds Pope Marcellinus as the 30th pope.source
• 308Maxentius institutes toleration of the Christians in his territories.source
• 309April 18 – Eusebius succeeds Marcellus I as the 31st pope, but is himself banished on August 17 to Sicily (these events may have also taken place in 310).source
• 309Pope Marcellus I is banished from Rome by Emperor Maxentius.source
• 310Maximinus Daza, caesar under Emperor Galerius, is acclaimed augustus by his troops. Galerius is forced to recognize him as co-ruler of the East. The Roman Empire is thus divided between seven simultaneous emperors: Galerius (East), Maximinus II (East), Licinius (Middle), Constantine I (West), Maximian (West), Maxentius (Italy), and Domitius Alexander (Africa).source
• 311April 30 – On his deathbed, Emperor Galerius declares religious freedom and issues the Edict of Serdica, ending the Diocletianic Persecution of Christians in the eastern half of the Roman Empire.source
• 311July 2 – Pope Miltiades succeeds Eusebius as the 32nd pope of Rome.source
• 311Maximinus recommences the persecution of Christians, having encouraged his subjects to petition him to do so.source
• 311The Donatist schism begins in the African Church.source
• 311Maximinus Daza and Licinius divide the Eastern Empire between themselves.source
• 312Constantine I promotes a policy of state sponsorship of Christianity, perhaps even becoming a Christian himself (see Constantine the Great and Christianity).source
• 312Constantine I adopts the words "in hoc signo vinces" as a motto, and has the letters X and P (the first letters of the Greek word Christ) emblazoned on the shields of his soldiers.source
• 312The Council of Carthage supports Donatism, which espouses a rigorous application and interpretation of the sacraments. These doctrines will be condemned by the Council of Arles (314).source
• 313February 3 – Edict of Milan: Constantine the Great and co-emperor Licinius meet at a conference in Mediolanum (modern Milan). They proclaim a policy of religious freedom for all, ending the persecution of Christians in the Roman Empire and returning property confiscated from Christians. The edict is posted in Nicomedia on June 13.source
• 313February: Emperors Constantine I and Licinius convene in Mediolanum (modern Milan). Licinius marries Constantine's half-sister Constantia, and they issue the Edict of Milan. This edict ends the Great Persecution against the Christians and is the first piece of legislation in western history to decree freedom of religion. It also returns property confiscated from Christians. The edict is posted in Nicomedia on June 13.source
• 313October 2 – Lateran Synod: Donatism is declared a heresy.source
• 313Arius preaches of the human nature of Jesus.source
• 314January 10 – Pope Miltiades' reign ends.source
• 314January 31 – Pope Sylvester I succeeds Pope Miltiades as the 33rd pope.source
• 314August 30 – Council of Arles: Confirms the pronouncement of Donatism as a schism, and passes other canons.source
• 314Alexander becomes Bishop of Byzantium.source
• 314Synod of Ancyra: Consulting a magician is declared a sin earning five years of penance.source
• 315The lamb becomes the symbol of Jesus in Christian art.source
• 315Eusebius becomes bishop of Caesarea (approximate date).source
• 315Constantine I dedicates the Basilica of Maxentius and installs a large statue of himself inside it.source
• 316At the request of the Christians, Constantine I attempts to end the schism with the Donatist sect.source
• 316Emperor Constantine the Great issues an edict, prohibiting the punishment of slaves by crucifixion and facial branding.source
• 317March 1 – Emperor Constantine the Great and co-emperor Licinius elevate their sons Crispus, Constantine II and Licinius II to Caesars. After this arrangement Constantine rules the dioceses Pannonia and Macedonia, and establishes his residence at Sirmium, from where he prepares a campaign against the Goths and Sarmatians.source
• 317Licinius recognizes Constantine I as senior emperor and executes Valerius Valens.source
• 318Gregory the Illuminator appoints his son Aristax as successor in the patriarchate of Armenia.source
• 318Constantine the Great is given the title Brittanicus Maximus, for successful engagements in Britain.source
• 318Emperor Constantine the Great gives the ancient Roman town Drepana (Asia Minor) the name Helenopolis, after his mother Helena, and builds a church in honour of the martyr St. Lucian.source
• 319Arius travels to Nicomedia at the invitation of Bishop Eusebius, after having been accused of heresy and condemned by Alexander, the Patriarch of Alexandria. This gives rise to the Arian Controversy.source
• 319Christianity is introduced in Colchis, present-day Georgia.source
• 320Licinius reneges on the religious freedom promised by the Edict of Milan, and begins a new persecution of Christians in the Eastern Roman Empire. He imprisons Christians, confiscates their properties and destroys churches.source
• 321Calcidius translates Plato into Latin.source
• 321The Christian Church is allowed to hold property.source
• 321A synod held in Alexandria condemns Arianism.source
• 324June – The earliest known use of the Greek word monachós to refer to a monk is made in a petition filed in Egypt by a man named Aurelius Isidorus, a man from the town of Karanis in Egypt.source
• 324November 8 – Emperor Constantine declares his son, Flavius Julius Constantius, to the rank of caesar, designating Flavius as his successor. Flavius will ascend the throne as Constantine the Second in 337 AD.source
• 324November 9 – Dedication of the Lateran Basilica in Rome.source
• 325May 20 – First Council of Nicaea: Constantine summons an ecumenical council of bishops in Nicaea (Turkey). The Nicene Creed, adopted on June 19, declares that the members of the Trinity (the Father, the Son, and the Holy Spirit) are equal. The council decides that Easter is celebrated on the first Sunday after the first full moon after the vernal equinox. Arius is exiled to Illyria; his works are confiscated and consigned to the flames.source
• 325The Colossus of Constantine in the Basilica of Maxentius and Constantine, Rome, is perhaps remodelled at about this date. (The remains are moved to the Palazzo dei Conservatori, Rome, in the 15th century).source
• 326September 14 (traditional date) – Helena, mother of Constantine I, discovers the so-called True Cross and the Holy Sepulchre (Jesus's tomb) in Jerusalem. On her pilgrimage, which begins about this year, she pauses on the Aegean island of Patmos, where she is said to found the church of Panagia Ekatontapiliani.source
• 326Emperor Constantine the Great travels to Rome to celebrate the 20th anniversary of his accession to power, but while en route at Pola he orders his older son, Crispus Caesar, to be executed, possibly on charges of adultery. Later, Fausta, second wife of Constantine I, is also executed by being suffocated or boiled in a hot bath.source
• 326Helena tells Constantine that he must atone for executing his son and wife by building churches, and at about this date construction begins on Old St. Peter's Basilica, the first church on the traditional site of Saint Peter's tomb in Rome, and on the basilica of Golgotha on Calvary outside Jerusalem. He also commissions construction of the Church of the Nativity in Bethlehem (dedicated 339).source
• 326Christianity is introduced to the Kingdom of Iberia (modern-day Georgia) by Saint Nino (approximate date).source
• 327Approximate traditional date – Helena, mother of Constantine, returning from her pilgrimage to the Holy Land, founds Stavrovouni Monastery on Cyprus.source
• 329Roman restrictions on joining the clergy are initiated.source
• 330Pagan temples begin to be progressively abandoned, destroyed or left to fall into disrepair, save those that are transformed into churches.source
• 330The Bible is translated into the Gothic language by Wulfila.source
• 330Frumentius is the first bishop of Ethiopia (approximate date).source
• 330Eustathius, Patriarch of Antioch, is banished to Trajanopolis.source
• 331Eusebius of Caesarea writes the Onomasticon.source
• 331Constantine I dedicates the Church of the Holy Apostles in Constantinople.source
• 331The Fifty Bibles of Constantine are commissioned for use in Constantinople.source
• 331Emperor Constantine the Great vigorously promotes Christianity, confiscating the property and valuables of a number of pagan temples throughout the Roman Empire.source
• 333December 25 – Constantine I elevates his youngest son Constans to the rank of Caesar at Constantinople.source
• 335September 13 – The Church of the Holy Sepulchre in Jerusalem is consecrated.source
• 335September 14 – Emperor Constantine I consecrates the Church of the Holy Sepulchre in Jerusalem.source
• 335Constantine I reinstates the Alexandrian priest Arius (declared a heretic at the First Council of Nicaea in 325) in a synod at Jerusalem about a year before Arius' death.source
• 335Hannibalianus, nephew of Constantine I, is made Rex Regum ("King of Kings of the Pontic people").source
• 335First Synod of Tyre: Constantine I convenes a gathering of bishops at Tyre to depose and exile Patriarch Athanasius of Alexandria.source
• 336January 18 – Pope Mark succeeds Pope Sylvester I as the 34th pope of the Catholic Church.source
• 336Pope Mark begins to build the basilica of San Marco; the church is devoted to St. Mark.source
• 337February 6 – A 4-month papal vacancy ends; Pope Julius I succeeds Pope Mark, as the 35th pope.source
• 337June 17 – Constantius II announces the restoration of Athanasius, as Patriarch of Alexandria.source
• 337September 9 – Constantine II, Constantius II, and Constans succeed their father Constantine I as co-emperors. The Roman Empire is divided between the three Augusti.source
• 337Paul I becomes Patriarch of Constantinople.source
• 337Christianity is declared an official religion in Caucasian Iberia, marking the rise of Christianity in Georgia.source
• 338Non-Christians are persecuted by the Roman Empire as pagans.source
• 338Eusebius of Nicomedia becomes Patriarch of Constantinople, after Paul I is banished.source
• 339Pope Julius I gives refuge in Rome to the Alexandrian patriarch Athanasius, who is deposed and expelled during the First Synod of Tyre (see 335).source
• 339Eusebius of Nicomedia is made bishop of Constantinople, while another Arian succeeds Athanasius as bishop of Alexandria, under the name Gregory.source
• 340Wulfila evangelizes among the Goths for 7 years.source
• 340Acacius succeeds Eusebius as bishop in the see of Caesarea.source
• 341Coptic Christianity is introduced into Ethiopia by the Syrian apostle Frumentius. He and his colleague Aedesius ware captured by Ethiopians a year or two ago, and have become civil servants at the Aksumite court of King Ezana. Ezana is impressed with Frumentius' teachings and converts to Christianity. Frumentius becomes the first Bishop of Axum and encourages the Christian merchants present in the country to practise their faith openly.source
• 341Paul I is restored as Patriarch of Constantinople.source
• 341The Council of Encaenia is held in Antioch.source
• 341Emperor Constans I bans pagan sacrifices and magic rituals, under penalty of death.source
• 342February 15 – The original Hagia Sophia is dedicated in Constantinople.source
• 342Paul I, Patriarch of Constantinople, is deposed and replaced by Macedonius I.source
• 343Pope Julius I tries to unite the Western bishops against Arianism by convoking the Council of Serdica, which acknowledges the pope's supreme authority and grants him the right to judge cases involving the legal possession of episcopal sees, but only Western and Egyptian bishops attend, and Arianism remains strong.source
• 344Bishop Eustorgius I brings relics of the Three Magi from Constantinople to Milan, according to a 12th century legend.source
• 345Constans orders the Basilica di Santa Tecla to be constructed in Milan.source
• 346The Visigoths are converted to Arianism by Wulfila.source
• 346Emperor Constans I uses his influence to secure the return of Athanasius. He is restored as Patriarch of Alexandria, and documents are compiled relating to his expulsion, under the title Apology Against the Arians.source
• 346Julius Firmicus Maternus writes De erroribus profanarum religionum.source
• 346Macedonius I, Patriarch of Constantinople, is deposed again by Paul I.source
• 347The Council of Philippopolis is held as the result of Eastern bishops leaving the Council of Sardica. In Philippopolis (Bulgaria), they excommunicate Pope Julius, and as a result, the Arian controversy is perpetuated.source
• 347Council of Sardica: An attempt is made to resolve the Arian controversy, and ground rules for bishops are laid down.source
• 350January 18 – Western Roman Emperor Constans I makes himself extremely unpopular; one of his generals, Magnentius, is proclaimed emperor at Augustodunum in the Diocese of Galliae, with the support of the army on the Rhine frontier.source
• 351Macedonius is restored as Patriarch of Constantinople.source
• 353Constantius II assembles a conciliabulum at Arles, and condemns Athanasius as Patriarch of Alexandria.source
• 353Wang Xizhi, Chinese calligrapher, produces "Preface to the Poems Composed at the Orchid Pavilion" in running script style. It becomes a model for future calligraphers.source
• 354Libanius becomes a teacher of rhetoric in Antioch; his students include John Chrysostom and Theodore of Mopsuestia.source
• 355Pope Liberius refuses to sign a condemnation of Athanasius, Patriarch of Alexandria, imposed at Milan by Constantius II. Liberius is exiled to Beroea (Greece) and replaced by Felix II. He becomes an antipope and bishop of Rome.source
• 356February 19 – Emperor Constantius II issues a decree closing all pagan temples in the Roman Empire, and ordering the banishment once again of the anti-Arian patriarch of Alexandria, Athanasius. He tries to have him arrested during a vigil service, but Athanasius flees to the Nitrian desert in Upper Egypt.source
• 357Ammianus Marcellinus describes the Pantheon as being "rounded like the boundary of the horizon and vaulted with a beautiful loftiness".source
• 357At about this date, the relics of St Andrew the Apostle are taken from Patras to Constantinople by order of the Emperor Constantius II, and deposited in the Church of the Holy Apostles.source
• 357Late in the year Pope Liberius travels to Sirmium (Pannonia) and agrees to sign documents that effectively undo the Nicene Creed (which implicitly disavows Arianism) and to sever his relationship with the former Alexandrian patriarch Athanasius, who is replaced as patriarch of Alexandria by his Arian opponent George of Cappadocia.source
• 358Constantius II recalls Pope Liberius to Rome, where he receives a joyous welcome from the Christians. Antipope Felix II prudently retires to his estate near Porto (Portugal).source
• 358The last universally binding decision, of the Great Sanhedrin, establishes a fixed Hebrew calendar.source
• 358Eudoxius becomes Patriarch of Antioch.source
• 359July – Emperor Constantius II convenes the Council of Rimini, to resolve the crisis over Arianism in the Church. Some 400 bishops of the Western portion of the Roman Empire attend, while the Eastern bishops simultaneously hold a meeting at Seleucia. Given Saint Jerome's comment that, "The whole world groaned in astonishment to find itself Arian", it appears to have failed. Pope Liberius rejects the new creed at Rimini.source
• 359The Sarcophagus of Junius Bassus, in the Old St. Peter's Basilica, Vatican, is made (approximate date).source
• 36014 February – The first Hagia Sophia church is consecrated in Constantinople.source
• 360Council of Constantinople (360): Emperor Constantius II requests a church council, at Constantinople; both the eastern and western bishops attend the meeting. Ulfilas also attends the council and endorses the resulting creed. After the council several homoiousian bishops are deposed or banished, including Macedonius I of Constantinople and Cyril of Jerusalem.source
• 360At about this date, Ligugé Abbey in France is founded for the monastic Order of Saint Benedict by Martin of Tours, under dispensation from Bishop Hilary of Poitiers.source
• 360Roman authorities in Britain export wheat to supply the legions on the Rhine; they have encouraged production of wheat for that purpose.source
• 361December 11 – Julian becomes sole emperor of the Roman Empire; he rules from Constantinople, and tries to restore paganism. Constantius II is buried in the Church of the Holy Apostles.source
• 361December 24 – George of Cappadocia, the Arian intruding bishop of Alexandria, is murdered in his see and Athanasius of Alexandria returns to his native city in triumph.source
• 361Gregory Nazianzus (Saint Gregory the Theologian) returns to Nazianzus and is appointed a priest by his father, who wants him to assist local Christians.source
• 361Construction of the Monastery of Saint Anthony in the Eastern Desert of Egypt begins.source
• 361Emperor Julian tries to organize a pagan church and substitute it for Christianity. Pope Liberius repudiates the Arian creed, and declares that the Council of Ariminum has no authority to issue decrees.source
• 362February 21 – Athanasius returns to Alexandria and convenes a council, at which he appeals for unity among Christians who differ in terminology, but Emperor Julian orders Athanasius to leave Alexandria. He will remain in exile in Upper Egypt, until after Julian's death the next year.source
• 363The Council of Laodicea, which deals with constricting the conduct of church members, is held. The major canon approved by this council is Canon 29, which prohibits resting on the Sabbath (Saturday), restricting Christians to honoring the Lord on Sunday.source
• 363Mar Mattai Monastery is founded on Mount Alfaf.source
• 364The Council of Laodicea decides some disciplinary questions of the church and attempts to establish the Biblical canon, but fails.source
• 365Basil of Caesarea becomes presbyter of Caesarea.source
• 365Emperor Valens orders the expulsion of the Alexandrian bishop Athanasius from his see, but instead of going into exile Athanasius, now about 67, moves to the outskirts of Alexandria.source
• 367August 4 – Gratian receives the title of Augustus under his father, Valentinian I.source
• 367November 16 – Antipope Ursicinus is banished by the praefecti to Gaul.source
• 367Epiphanius of Salamis becomes bishop of Salamis, Cyprus.source
• 367The first Listing of the New Testament (Bible) is made by St. Athanasius of Alexandria.source
• 367Valentinian I declares that Christians will not be forced into gladiator training schools.source
• 367Emperor Valens is baptized by Eudoxius of Antioch.source
• 369Wulfila creates a Gothic alphabet composed of letters based on Greek and Roman letters, as well as some Germanic runes. He converts the Goths to Arian Christianity.source
• 370Demophilus of Constantinople becomes Patriarch of Constantinople, although his position is disputed by Evagrius of Constantinople.source
• 370Basil the Great becomes bishop of Caesarea (Cappadocia).source
• 371Martin of Tours becomes bishop of Tours (approximate date).source
• 371Augustine of Hippo, age 17, travels to Carthage to continue his education in rhetoric.source
• 372Buddhism is adopted as the official religion of Gorguryeo.source
• 372Gregory of Nyssa becomes bishop of Nyssa.source
• 372Saint Augustine adopts Manichaeism.source
• 373Saint Martin of Tours undertakes the Christianization of Gaul.source
• 373Quintus Aurelius Symmachus becomes proconsul of Africa, and is made a member of the pontifical college.source
• 373Emperor Valens is converted to Arianism, and orders the persecution of Trinitarian Christians in the Roman East.source
• 374December 7 – The people of Milan astonish Ambrosius, governor of Aemilia-Liguria, by acclaiming him bishop. He is the second son of the former praetorian prefect of Gaul, and becomes a creative thinker whose ideas will provide the paradigm for medieval church-state relations.source
• 375Gratian, advised by his chief advisor Ambrosius, begins a systematic persecution of the pagans. He confiscates the fortunes of the temples and adds the money to the Imperial Treasury. He proscribes Arianism and Donatism.source
• 375The Maronite Church is founded by Saint Maron in Lebanon.source
• 375The Talmud of Babylon is written by Rav Ashi. This commentary on the Mishnah contains approximately 2.5 million words on 5.894 pages.source
• 375The first two Korean Buddhist temples are built.source
• 378Gregory of Nazianzus is ordained bishop of Constantinople.source
• 378Pope Damasus I is accused of adultery but is exonerated by Gratian.source
• 378Fritigern sends a Christian priest to the Roman camp with an offer of terms and a letter for Valens. The peace overtures are rejected.source
• 379Gratian renounces the title Pontifex Maximus.source
• 379John Chrysostom writes a book on the Christian education of children.source
• 379Gregory Nazianzus becomes Patriarch of Constantinople, and is wounded when he is attacked by a mob of heretics.source
• 380February 27 – Edict of Thessalonica: Theodosius I, with co-emperors Gratian and Valentinian II, declare their wish that all Roman citizens convert to trinitarian Christianity, in accordance with the patriarchs of Rome and Alexandria, implicitly rejecting the Arianism of the patriarch of Constantinople as heretical.source
• 380Emperor Theodosius I is baptized.source
• 380A cathedral is built in Augusta Treverorum.source
• 380Ticonius writes a commentary on the Bible's Book of Revelation.source
• 380The Council of Saragossa is held; Spanish and Aquitanian bishops condemn the teachings of Priscillianism.source
• 381John Chrysostom becomes a deacon.source
• 381Emperor Gratian moves the capital to Mediolanum (modern-day Milan). Because of his Christian beliefs, he eliminates Pontifex Maximus as Imperial title. Gratian also refuses the robe of office, insulting the pagan aristocrats of Rome.source
• 381First Council of Constantinople (some authorities date this council to 383): Theodosius I calls a general council to affirm and extend the Nicene Creed, and denounce Arianism and Apollinarism. Most trinitarian churches consider this an Ecumenical council.source
• 381Timothy succeeds Peter II as Patriarch of Alexandria.source
• 381Nectarius succeeds Gregory Nazianzus as Archbishop of Constantinople.source
• 381Council of Aquileia: Ambrose and the council depose the Arian bishops Palladius of Ratiaria and Secundianus of Singidunum.source
• 381The Gallic city of Cularo is renamed Gratianopolis (later Grenoble), in honor of Gratian having created a bishopric.source
• 381Flavian succeeds Meletius as Patriarch of Antioch.source
• 382The Council of Rome establishes Biblical canon in the Catholic Church. Pope Damasus I commissions a revision of the Vetus Latina, eventually resulting in the Vulgate of Jerome.source
• 382The first sermons declaring the virginity of Mary are given by John Chrysostom.source
• 383By the order of Theodosius I, Eunomius of Cyzicus is banished to Moesia.source
• 383First Council of Constantinople (some authorities date this council to 381): Theodosius I calls a general council to affirm and extend the Nicene Creed, and denounce Arianism and Apollinarism. Most trinitarian Christian churches consider this an Ecumenical council.source
• 384December 17 – Pope Siricius succeeds Damasus I as the 38th pope. He takes the title Pontifex Maximus, after it is relinquished by the late emperor Gratian.source
• 384An edict of Theodosius I closes pagan temples in the Nile Valley (Egypt).source
• 384Ambrosius refuses the request of Empress Justina for a church in Milan, where she can worship according to her Arian belief.source
• 384Jerome, Christian prophet, writes his celebrated letter "De custodia virginitatis" (vow of virginity) to Eustochium, daughter of the ascetic Paula. He has by this time completed his Vulgate translation of the Gospels.source
• 384The Gallaeci or Gallic woman Egeria concludes her Christian pilgrimage to the Holy Land at about this date; her narrative of it, the Itinerarium Egeriae, may be the earliest surviving formal writing by a woman in western European culture.source
• 384A synod is held in Bordeaux (France).source
• 385Priscillian, Spanish bishop, is accused of Manichaeism and magic, and beheaded at Trier . He becomes the first person in the history of Christianity to be executed for heresy.source
• 385Theophilus becomes Patriarch of Alexandria.source
• 385Pope Siricius issues the Directa Decretal, proclaiming the primacy of Rome and the priestly obligation of celibacy.source
• 385The Roman synod exiles the prophet Jerome, who has incorporated ideas first propounded by the Roman statesman Cicero. He departs for Egypt, Bethlehem, and Jerusalem, accompanied by the Christian ascetic Paula, who will edit Jerome's translation of the Bible, which becomes the Latin Vulgate.source
• 386John Chrysostom becomes a presbyter; he also writes eight Homilies entitled "Adversus Iudaeos" ("Against the Jews").source
• 386Saint Ambrose defends the rights of the Catholic Church with respect to those of the State.source
• 386Augustine converts to Christianity. He ends his marriage plans after hearing a sermon on the life of Saint Anthony.source
• 386Sumela Monastery is established in Asia Minor.source
• 387Augustine is baptized on Easter Vigil by Saint Ambrose, Bishop of Milan.source
• 388Paternus becomes bishop of the Episcopal see of Braga (Portugal).source
• 388Isaac, age 50, is named Catholicos (spiritual head) of the Armenian Apostolic Church.source
• 390Jerome, having finished the Latin translation of the New Testament, begins translating the Old Testament.source
• 390The Kama Sutra is revised by Vatsyayana.source
• 390Ambrose retires to Milan (residence of Theodosius I) and refuses to celebrate a mass in the emperor's presence, until he repents for ordering the massacre in Thessalonica. Theodosius, filled with remorse, kneels in humility and strips off his royal purple, before the altar of the cathedral in Milan, humbling himself before the church.source
• 391Emperor Theodosius I establishes Christianity as the official state religion. All non-Christian temples in the Roman Empire are closed. The eternal fire in the Temple of Vesta at the Roman Forum is extinguished, and the Vestal Virgins are disbanded.source
• 391Patriarch Theophilus destroys all pagan temples in Alexandria under orders from Theodosius I. Christians go on an iconoclastic rampage, smashing religious symbols or monuments through the city and destroying the Temple of Serapis. The "Order of Monks" known as the Parabalani take charge of patrolling the streets.source
• 392August 22 – Arbogast nominates Eugenius, Roman teacher of rhetoric, as the next emperor of the Western Roman Empire. He sends ambassadors to Theodosius's court asking for his recognition.source
• 392November 8 – Theodosius I issues an edict reinforcing the prohibition of prayers or sacrifices at non-Christian temples, leading to the persecution of pagans and the end of the almost 2,000-year-old Eleusinian Mysteries. He also bans items of pagan spiritual significance that could be used in the home, such as incense or spiritual figures.source
• 393January 23 – Emperor Theodosius I proclaims his son Honorius, age 8, co-ruler (Augustus) of the Western Roman Empire.source
• 393Synod of Hippo: A council at Hippo Regius (Algeria) is hosted by the Church. The bishops approve a canon of Sacred Scripture that correspond to the Roman Catholic Church.source
• 394The Council of Bagaï in Africa brings 310 Donatist bishops together.source
• 394In Rome, the sacred fire stops burning (see Vesta and Vestal Virgins).source
• 394Epiphanius of Salamis attacks Origen's followers and urges John II, Bishop of Jerusalem, to condemn his writings.source
• 395Augustine, age 40, becomes bishop of Hippo Regius (modern Algeria). His assignment is the reunification of the Roman Catholic Church in Africa, primarily focusing on the Donatist movement led by Primianus of Carthage.source
• 396Lü Guang claims the title "Heavenly Prince" (Tian Wang), signifying his claim to the Later Liang Kingdom.source
• 397August 28 – Council of Carthage: The biblical canon is definitely declared.source
• 397September 7 – First Council of Toledo: Hispanic bishops, including Lampius, condemn Priscillianism.source
• 397November 13 – John Chrysostom is appointed Archbishop of Constantinople.source
• 397Mor Gabriel Monastery is founded and located on the Tur Abdin plateau near Midyat (Turkey).source
• 397Scottish missionary Ninian establishes a church (Candida Casa) at Whithorn, and begins his work among the Picts.source
• 397Sulpicius Severus writes the earliest biography of Martin of Tours, the first known "life of a saint" ever written.source
• 397Augustine of Hippo begins his Confessions, an autobiography that recounts his intellectual and spiritual development.source
• 398John Chrysostom, Archbishop of Constantinople, receives a delegation of clergy who want to close the pagan temples at Gaza (Palestine) where worshippers are openly defying the law. John works through the eunuch Eutropius, who has great power over emperor Arcadius, and within a week an imperial Constitution is issued closing the Roman temples, but the official appointed to execute this order is bribed.source
• 398Augustine of Hippo completes his Confessions, an autobiography that recounts his intellectual and spiritual development.source
• 399Anastasius I succeeds Siricius as the 39th pope. He seeks to reconcile the churches of Rome and Antioch. Anastasius also condemns the doctrine of Origen.source
• 399Flavius Mallius Theodorus becomes Roman consul and official at the imperial court of emperor Arcadius.source
• 399Flavian I is acknowledged as legitimate bishop of Antioch by the Church of Rome.source