The Gospel of John refers to an unnamed "Beloved Disciple" of Jesus who bore witness to the gospel's message. The editors of the Gospel, who record the Beloved Disciple's death, seem interested in the author's anonymity. Apparently this disciple of Jesus had not been well known, but had greatly outlived Peter.
The apostle John was a historical figure, one of the "pillars" of the Jerusalem church after Jesus' death. Many scholars believe that John was martyred along with his brother, as Jesus predicts in Mark (Mark 10:39, Acts 12:1-2). The tradition that John lived to old age in Ephesus and that he wrote this gospel date from the late second century. Modern scholars do not regard John to have authored any of the texts ascribed to him.
Christian tradition says that John the Evangelist was one of Christ's original twelve apostles; the only one to live into old age; and not martyred for his faith. John the Evangelist is associated with Ephesus, where he is said to have lived and been buried. Some believe that after a short life he was exiled to Patmos, where he wrote the Book of Revelation. However this is a matter of debate, with some attributing authorship to John of Patmos or John the Presbyter. It also debated whether John the Evangelist is the same as St. John the Apostle.
John was the son of Zebedee and Salome, and the brother of James the Greater. In the Gospels the two brothers are often called after their father "the sons of Zebedee" and received from Christ the honourable title of Boanerges, i.e. "sons of thunder" (Mark 3:17). Originally they were fishermen and fished with their father in the Lake of Genesareth. According to the usual and entirely probable explanation they became, however, for a time disciples of John the Baptist, and were called by Christ from the circle of John's followers, together with Peter and Andrew, to become His disciples (John 1:35-42). The first disciples returned with their new Master from the Jordan to Galilee and apparently both John and the others remained for some time with Jesus (cf. John ii, 12, 22; iv, 2, 8, 27 sqq.). Yet after the second return from Judea, John and his companions went back again to their trade of fishing until he and they were called by Christ to definitive discipleship (Matthew 4:18-22; Mark 1:16-20). In the lists of the Apostles John has the second place (Acts 1:13), the third (Mark 3:17), and the fourth (Matthew 10:3; Luke 6:14), yet always after James with the exception of a few passages (Luke 8:51; 9:28 in the Greek text; Acts 1:13).
From James being thus placed first, the conclusion is drawn that John was the younger of the two brothers. In any case John had a prominent position in the Apostolic body. Peter, James, and he were the only witnesses of the raising of Jairus's daughter (Mark 5:37), of the Transfiguration (Matthew 17:1), and of the Agony in Gethsemani (Matthew 26:37). Only he and Peter were sent into the city to make the preparation for the Last Supper (Luke 22:8). At the Supper itself his place was next to Christ on Whose breast he leaned (John 13:23, 25). According to the general interpretation John was also that "other disciple" who with Peter followed Christ after the arrest into the palace of the high-priest (John 18:15). John alone remained near his beloved Master at the foot of the Cross on Calvary with the Mother of Jesus and the pious women, and took the desolate Mother into his care as the last legacy of Christ (John 19:25-27). After the Resurrection John with Peter was the first of the disciples to hasten to the grave and he was the first to believe that Christ had truly risen (John 20:2-10).
When later Christ appeared at the Lake of Genesareth John was also the first of the seven disciples present who recognized his Master standing on the shore (John 21:7). The Fourth Evangelist has shown us most clearly how close the relationship was in which he always stood to his Lord and Master by the title with which he is accustomed to indicate himself without giving his name: "the disciple whom Jesus loved".
After Christ's Ascension and the Descent of the Holy Spirit, John took, together with Peter, a prominent part in the founding and guidance of the Church. We see him in the company of Peter at the healing of the lame man in the Temple (Acts 3:1 sqq.). With Peter he is also thrown into prison (Acts 4:3). Again, we find him with Peter visiting the newly converted in Samaria (Acts 8:14).
We have no positive information concerning the duration of this activity in Palestine. Apparently John in common with the other Apostles remained some twelve years in this first field of labour, until the persecution of Herod Agrippa I led to the scattering of the Apostles through the various provinces of the Roman Empire (cf. Acts 12:1-17). Notwithstanding the opinion to the contrary of many writers, it does not appear improbable that John then went for the first time to Asia Minor and exercised his Apostolic office in various provinces there. In any case a Christian community was already in existence at Ephesus before Paul's first labours there (cf. "the brethren", Acts 18:27, in addition to Priscilla and Aquila), and it is easy to connect a sojourn of John in these provinces with the fact that the Holy Ghost did not permit the Apostle Paul on his second missionary journey to proclaim the Gospel in Asia, Mysia, and Bithynia (Acts 16:6 sq.). There is just as little against such an acceptation in the later account in Acts of St. Paul's third missionary journey. But in any case such a sojourn by John in Asia in this first period was neither long nor uninterrupted. He returned with the other disciples to Jerusalem for the Apostolic Council (about A.D. 51). St. Paul in opposing his enemies in Galatia names John explicitly along with Peter and James the Just (the brother of Jesus) as a "pillar of the Church", and refers to the recognition which his Apostolic preaching of a Gospel free from the law received from these three, the most prominent men of the old Mother-Church at Jerusalem (Galatians 2:9). When Paul came again to Jerusalem after the second and after the third journey (Acts 18:22; 21:17 sq.) he seems no longer to have met John there. Some wish to draw the conclusion from this that John left Palestine between the years 52 and 55.
Of the other New-Testament writings, it is only from the three Epistles of John and the Apocalypse that anything further is learned concerning the person of the Apostle. We may be permitted here to take as proven the unity of the author of these three writings handed down under the name of John and his identity with the Evangelist. Both the Epistles and the Apocalypse, however, presuppose that their author John belonged to the multitude of personal eyewitnesses of the life and work of Christ (cf. especially 1 John 1:1-5; 4:14), that he had lived for a long time in Asia Minor, was thoroughly acquainted with the conditions existing in the various Christian communities there, and that he had a position of authority recognized by all Christian communities as leader of this part of the Church. Moreover, the Apocalypse tells us that its author was on the island of Patmos "for the word of God and for the testimony of Jesus", when he was honoured with the heavenly Revelation contained in the Apocalypse (Revelation 1:9).
Collectively, the Gospel, the three Epistles, and Revelation are known as Johannine literature, and there is some internal textual evidence to suggest they may have been authored by the same person (see textual criticism). Of the Johannine literature, Revelation bears the least grammatical similarity to the Gospel. No scholar believes that the Apostle John wrote none of these texts . However, traditional Christian thought on the subject points to St. John the Apostle as the author of the Gospel, the three Epistles and the Book of Revelation that bear his name .
Numerous modern scholars dispute that these works were by the same person.  The most widely accepted view is that - whether or not the same man wrote all the Johannine literature - it all came out of the same community in Asia Minor, which had some connection to John the Evangelist, John of Patmos, and John the Presbyter.
The author of the Gospel of John never identifies himself. He is generally assumed to be the "beloved disciple" repeatedly referred to in the Gospel. The author of this Gospel is also sometimes presumed to be the author of 1 John, and also, more rarely, of 2 John and 3 John. The 4th century Council of Rome decreed that the author of 1 John and that of 2 and 3 John should be regarded as distinct individuals.
Evangelical Christians, orthodox Roman Catholic scholarship, and the entire Eastern Orthodox Church attributes all of the Johanine literature to the same individual, the "Holy Apostle and Evangelist, John the Theologian", whom it identifies with the "Beloved Disciple" in the Gospel of John.
The 27 December feast is found in the Syriac Breviary of the end of the fourth century and the Martyrology of Jerome. But at present Saint John is celebrated on a wide variety of dates in Eastern rites: 29 December for Armenians, 30 December for Copts, 7 May for Syrians and 26 September for Christians of Byzantine Rite.
The Tridentine Calendar also had on 6 May a feast of "St John before the Latin Gate", associated with a tradition recounted by Saint Jerome that St John was brought to Rome during the reign of the Emperor Domitian, and was thrown in a vat of boiling oil, from which he was miraculously preserved unharmed. A church, San Giovanni a Porta Latina, dedicated to him was built near the Latin Gate (Porta Latina) of Rome, the traditional scene of this event. The feast is supposed to commemorate the dedication of this church, and is first mentioned in the Sacramentary of Adrian I (772-95). Pope John XXIII removed this feast from the General Roman Calendar in 1960, along with various other second feasts of a single saint.
St. John the Evangelist is (along with St. John the Baptist) a Patron Saint of the fraternal society of Free and Accepted Masons (better known as the Freemasons).
Christian art usually represents St John with an eagle, symbolizing the heights to which he rises in the first chapter of his Gospel. The chalice as symbolic of St John, which, according to some authorities, was not adopted until the thirteenth century, is sometimes interpreted with reference to the Last Supper, again as connected with the legend according to which St. John was handed a cup of poisoned wine, from which, at his blessing, the poison rose in the shape of a serpent. Perhaps the most natural explanation is to be found in the words of Christ to John and James "My chalice indeed you shall drink" (Matthew 20:23).