John of Patmos

John of Patmos could be the author named as John in the Book of Revelation, the apocalyptic text forming the final book of the New Testament. The text of Revelation states that John was on Patmos, a Greek island where, by most biblical historians, he is considered to have been exiled as a result of anti-Christian persecution under the Roman emperor Domitian.
Since the Roman era, Christians and historians have considered the Book of Revelation's writer to be the Apostle John, author of the Gospel of John. However, a minority of senior clerics and scholars, such as Eusebius, recognize at least one further John as a companion of Jesus Christ, John the Presbyter "after an interval, placing him among others outside of the number of the apostles". Some Christian scholars since medieval times separate the disciple from Revelation's writer, John of Patmos/the Divine.

Book of Revelation

The author of the Book of Revelation identifies himself only as "John". Traditionally, this was often believed to be the same person as John, son of Zebedee, one of the apostles of Jesus, to whom the Gospel of John was also attributed. The early-2nd-century writer, Justin Martyr, was the first to equate the author of Revelation with John the Evangelist. Other early Christian writers, however, such as Dionysius of Alexandria and Eusebius of Caesarea, noting the differences in language and theological outlook between this work and the Gospel, discounted this possibility, and argued for the exclusion of the Book of Revelation from the canon as a result. The early Christian writer Papias appeared in his writings to distinguish between John the Evangelist and John the Elder, and many biblical scholars now contend that the latter was the author of Revelation.

Island of Patmos

John is considered to have been exiled to Patmos during a time of persecution under the Roman rule of Domitian in the late 1st century. states: "I, John, both your brother and companion in tribulation...was on the island that is called Patmos for the word of God and for the testimony of Jesus Christ." Adela Yarbro Collins, a biblical scholar at Yale Divinity School, writes:
Early tradition says that John was banished to Patmos by the Roman authorities. This tradition is credible because banishment was a common punishment used during the Imperial period for a number of offenses. Among such offenses were the practices of magic and astrology. Prophecy was viewed by the Romans as belonging to the same category, whether Pagan, Jewish, or Christian. Prophecy with political implications, like that expressed by John in the Book of Revelation, would have been perceived as a threat to Roman political power and order. Three of the islands in the Sporades were places where political offenders were banished.

According to Tertullian John was banished after being plunged into boiling oil in Rome and suffering nothing from it.