The son of Zebedee, a Galilean fisherman, and Salome, John and his brother James (James, Saint) were among the first disciples called by Jesus (Jesus Christ). In the Gospel According to Mark he is always mentioned after James and was no doubt the younger brother. His mother, Salome, was among those women who ministered to the circle of disciples. James and John were called by Jesus “Boanerges,” or “sons of thunder,” perhaps because of some character trait such as the zeal exemplified in Mark 9:38 and Luke 9:54 when John and James wanted to call down fire from heaven to punish the Samaritan towns that did not accept Jesus. John and his brother, together with Simon (Peter the Apostle, Saint) Peter, formed an inner nucleus of intimate disciples. In the Fourth Gospel, ascribed by early tradition to John, the sons of Zebedee are mentioned only once, as being at the shores of the lake of Tiberias when the risen Lord appeared; whether the “disciple whom Jesus loved” (who is never named) mentioned in this Gospel is to be identified with John (also not named) is not clear from the text.

John's authoritative position in the church after the Resurrection is shown by his visit with Peter to Samaria to lay hands on the new converts there. It is to Peter, James (not the brother of John but “the brother of Jesus”), and John that Paul successfully submitted his Gospel for recognition. What position John held in the controversy concerning the admission of the Gentiles to the church is not known; the evidence is insufficient for a theory that the Johannine school was anti-Pauline—i.e., opposed to granting Gentiles membership in the church.

John's subsequent history is obscure and passes into the uncertain mists of legend. At the end of the 2nd century, Polycrates, bishop of Ephesus, claims that John's tomb is at Ephesus, identifies him with the beloved disciple, and adds that he “was a priest, wearing the sacerdotal plate, both martyr and teacher.” That John died in Ephesus is also stated by Irenaeus (Irenaeus, Saint), bishop of Lyon c. AD 180, who says John wrote his Gospel and letters at Ephesus and Revelation at Patmos. During the 3rd century, two rival sites at Ephesus claimed the honour of being the Apostle's grave. One eventually achieved official recognition, becoming a shrine in the 4th century. In the 6th century the healing power of dust from John's tomb was famous (it is mentioned by the Frankish historian Gregory of Tours); at this time also, the church of Ephesus claimed to possess the autograph of the Fourth Gospel.

Legend was also active in the West, being especially stimulated by the passage in Mark 10:39, with its hints of John's martyrdom. Tertullian, the 2nd-century North African theologian, reports that John was plunged into boiling oil from which he miraculously escaped unscathed. During the 7th century, this scene was portrayed in the Lateran basilica and located in Rome by the Latin Gate; it is still annually commemorated on May 6. John's feast day otherwise is December 27. This belief that John did not die is based on an early tradition. In the original form of the apocryphal Acts of John (John, Acts of) (second half of the 2nd century) the Apostle dies; but in later traditions he is assumed to have ascended to heaven like Enoch and Elijah. A popular tradition known to Augustine declared that the earth over his grave heaved as if the Apostle were still breathing.

The legends that contributed most to medieval iconography are mainly derived from the apocryphal Acts of John. These Acts are also the source of the notion that John became a disciple as a very young man. Iconographically, the young, beardless type is early (as in a 4th century sarcophagus from Rome), and this type came to be preferred (though not exclusively) in the medieval West. In the Byzantine (Byzantine art) world the evangelist is portrayed as old, with long, white beard and hair, usually carrying his Gospel. His symbol as an evangelist is an eagle. On account of the inspired visions of the book of Revelation the Byzantine churches entitled him “the Theologian”; and the title appears in Byzantine manuscripts of Revelation but not in manuscripts of the Gospel.