John wrote the Gospel of John, the 1st, 2nd, and 3rd Epistles of John and Revelation.Some scholars dispute this because of the way the books are written, which goes to your question. The Gospel was written in what is considered perfect Greek, while the Epistles and Revelation, not so much. Revelation is considered to be written in a child-like manner by comparison, according to scholars who care about this factoid. These scholars discount the fact that the Gospel was written when John was in his early twenties, while Revelation was written when he was about a hundred years old. Not to mention the fact that he was writing all this during a vision of some pretty scary stuff.
The traditional view is that John is the author of all of it. He wrote the Gospel and the Epistles during the reign of Emperor Titus Flavius Domitian (24 Oct 51 AD - 18 Sept 96 AD). He was the Roman Emperor from 14 September 81 AD until his death.
John wrote Revelation while he was in exile on the island of Patmos, a small Greek island in the Aegean Sea located between the Southern Balkan and Anatolian Peninsulas. Today, that would be between Greece and Turkey. The island was uninhabited from the sixth century A.D. until 1088 A.D.
John was known by many names or references to describe his work. Most came after his death in order to distinguish him in his role with the early church and his office as an Apostle and writer of the books later to be included in the Bible.
Many of John’s designations, were given to him posthumously by the Catholic Church:
- John the son of Zebedee (Mark 3:17)
- Saint John the Apostle – Canonized by the Catholic Church as a Saint
- The Disciple whom Jesus loved- John gave himself this designation as he and Jesus were friends (John 13:23, 19:26, 21:7, 20:3, 21:20)
- John the Evangelist – Writer of the Gospel of John
- John of Patmos – Because of he was exiled on Patmos
- John the Theologian – His insight in the gospel book of John
- John the Presbyter – As writer of the Epistles
- The Eagle – The Gospel writers are associated with a Cherub Angel that is described as the four living creatures because it has four faces. A lion, eagle, calf and a man (Revelation 4:7)
- Eagle of Patmos
- John the Revelator – Writer of Revelations
- John the Seer – As one who has seen the future
- John the Divine – As recipient of the vision of Revelation
We should make note that the writers of the Gospels were not all Apostles. Matthew and John were, but not Luke or Mark. They wrote their books under the authority of Apostles. Luke was with Paul and Mark was with Peter.
They operated sort of like secretaries, who wrote down what the Apostles told them. Except in Luke’s case, he was part of an extension group that walked with Jesus from the beginning of Jesus’ walk from his baptism until his ascension, but he was not an Apostle. (Acts 1:21-26)
Paul was not among the original twelve Apostles. Neither was Matthias, who took Judas’ place. Paul was considered an Apostle, because he was charged by Jesus Himself on the Road to Damascus. This was a couple of years after Jesus had ascended to Heaven.
Paul was later confirmed by James, John and Peter, a.k.a. Cephas (John 1:42, 1 Corinthians 3:22, 15:5). Paul was sent by them to the Gentiles at Antioch (Acts 15:22-25, 29-31).
John and James are described as the first of four disciples to join Jesus (Matthew 4:18-22) Andrew and Peter being the first two. John and James were fishermen and worked with their father in Lake Genesareth.
In Revelation, John identifies himself several times (Revelation 1:1, 1:4, 1:9 22:8). John explicitly addresses Revelation to the seven churches in Asia Minor. These churches are located in seven different cities being, Ephesus, Smyrna, Pergamos, Thyatira, Sardis, Philadelphia and Laodicea (Revelation 1:4, 1:11).
The full title of the book of Revelation, according to the earliest manuscripts is: “The Apocalypse of Saint John the Divine “. The word ‘Apocalypse’ is a Greek word meaning‘uncovering’. The word divine is an old Anglican word meaning ‘theologian’. Revelation is also called “The Revelation of John”. Apocalypse in the Greek also means ‘lifting the veil’, disclosure or to be revealed.
In context, when John wrote this, the term Apocalypse was applied to disclosing information to privileged persons or something hidden from the majority of mankind. Today the term means “End of the World”.
Apocalypse in technical terms refers to the “revealed” will of God.
Some versions of Revelation will give the title “The Revelation of Jesus Christ”. This is done because John opens the text with the words “Revelation of Jesus Christ” but this was never part of the original title that John wrote on the book himself.