When you read Revelation, nowhere in the book does it state that John is in exile or imprisoned. He states that he is there for the Gospel. The tradition of John's exile was started by Augustine about 200 years after John lived. It appears that Revelation was written between A.D. 43-47.
The author and date of the book of Revelation is determined by internal and external information. First we will consider the internal and external data that helps us know that the apostle John wrote the book. Second, internal and external data is provided for the location where the book was written and the date of its writing.
The Author – The Internal Evidence
First, we will address the question, “Who wrote the book of Revelation?” The internal evidence of the book of Revelation is very important since the Word of God is without error and is the only source of truth. The external evidences can only support what is internal. The external can never override the internal truth. That is the operational principle by which we discover truths about the book of Revelation.
First, let’s examine what the book of Revelation says about its author. We will start with Revelation 1:4.
John to the seven churches that are in Asia: Grace to you and peace, from Him who is and who was and who is to come, and from the seven Spirits who are before His throne . . . Revelation 1:4 (NASB)
In verse 4 we are told that John wrote to the seven churches that are in Asia. Then in chapters two and three of the book of Revelation, the names of the seven churches are given and a message is given to them. This clearly reveals that the person identified as “John” is the author of the book. Paul, James, Peter, and Jude introduced themselves to their readers as the author of their letters or books at the beginning also.
Then in the ninth and tenth verses, that is, Revelation 1:9-10, John refers to himself as “I.”
I, John, your brother and fellow partaker in the tribulation and kingdom and perseverance which are in Jesus, was on the island called Patmos because of the word of God and the testimony of Jesus. I was in the Spirit on the Lord’s day, and I heard behind me a loud voice like the sound of a trumpet, Rev. 1:9-10 (NASB)
John then refers to himself as “I” once again in verse 10. In fact, he refers to himself in every chapter of the book of Revelation, except in chapters two and three which the author has already indicated he wrote. In the last chapter, Revelation 22:8, John uses his name once again. That means John referred to himself in the first chapters and the last chapter. The internal evidence states that John is the author of the entire book of Revelation.
Who is this John? Revelation 1:5 gives us a hint when the author says, “To Him who loves us and released us from our sins by His blood . . .” This is a very personal statement and is very similar to the opening verses of 1 John 1-9. In 1 John 1:1 the apostle John speaks about touching the Lord with his hands and seeing Him. It is important to recall that he was the disciple whom Jesus loved (John 13:23; 20:2; 21:7, 20). Consequently when the author speaks of Jesus as the One who loves us, it is a clue that this is the apostle John. No other author in the New Testament spoke in this manner of his personal relationship with Jesus as John did!
The Author – The External Evidence
The testimony of the early church fathers strongly supports the view that the apostle John is the author of the book of Revelation. For example, Irenaeus (A.D. 115 – 202) wrote in his book Against Heresies.
John also, the Lord’s disciple, when beholding the sacerdotal and glorious advent of His kingdom, says in the Apocalypse: “I turned to see the voice that spake with me. And being turned, I saw seven golden candlesticks . . .” 
Here he states that John was a disciple or apostle of Jesus Christ and that he wrote the Apocalypse or the book of Revelation. The verse that he quotes is Revelation 1:12. Then in numerous other passages in Against Heresies he refers to John and quotes from the book of Revelation.
Justin Martyr (A.D. 100 -166) wrote in Dialogue With Trypho chap 81 that the author of Revelation was John, an apostle of the Lord. He goes on to say,
John, one of the apostles of Christ, who prophesied, by a revelation that was made to him, that those who are in our Christ would dwell a thousand years in Jerusalem . . .
John Walvoord makes this statement about the authorship of Revelation,
The arguments for rejecting the apostolic authorship stem largely from the theological climate of the third century. At that time the Alexandrian School of Theology, including Dionysius, opposed the doctrine of the millennial kingdom which is plainly taught in chapter 20 with its reference to the thousand years. An attack by them on the authorship of John intended to weaken the force of the prophecy . . .
The substantiating evidence for any other author than John the Apostle, however, is almost entirely lacking. While notable scholars can be cited in support of divergent views, the proof dissipates upon examination. It seems clear that the early church attributed the book to John the Apostle. Justin Martyr quotes John’s view that Christ would dwell a thousand years in Jerusalem. Irenaeus quotes every chapter of the book of the Revelation. In like manner, Tertullian cites the author as “the Apostle John” and quotes from almost every chapter of the book. Hippolytus quotes extensively from chapters 17 and 18, attributing them to John the Apostle. Many other early fathers can be cited in similar fashion, such as Clement of Alexandria and Origen. The latter not only quotes from the book but confirms that John the Apostle was on the Isle of Patmos.
The first commentary on the book of Revelation to be preserved, written by Victorinus, regards John the Apostle as the author. 
The Muratorian Fragment reveals that most of the New Testament books were already recognized and accepted in the early part of the second century (A.D. 100-150). This would have been shortly after the apostle John died. The Muratorian Fragment was written about A.D. 170 since Polycarp (A.D. 69-155) refers to the Fragment himself. The Fragment is important since it recognizes most of the books of the New Testament and mentions their authors. Here is a partial quote from the Fragment. For a full quote visit The Muratorian Fragment.
As for the letters of Paul, they themselves show those who wish to understand from which place and for which cause they were directed. First of all [he wrote] to the Corinthians forbidding schisms and heresies; then to the Galatians [forbidding] circumcision; to the Romans he wrote at greater length about the order of the scriptures and also insisting that Christ was their primary theme. It is necessary for us to give an argued account of all these, since the blessed apostle Paul himself, following the order of his predecessor John, but not naming him, writes to seven churches in the following order: first to the Corinthians, second to the Ephesians, third to the Philippians, fourth to the Colossians, fifth to the Galatians, sixth to the Thessalonians, seventh to the Romans. But although [the message] is repeated to the Corinthians and Thessalonians by way of reproof, yet one church is recognized as diffused throughout the whole world. For John also, while he writes to seven churches in the Apocalypse, yet speaks to all. Moreover [Paul writes] one [letter] to Philemon, one to Titus and two to Timothy in love and affection; but they have been hallowed for the honor of the catholic church in the regulation of ecclesiastical discipline. 
It is important to notice that the Fragment states that John wrote to the seven churches of the Apocalypse. The external evidence strongly agrees with the internal evidence that the apostle John is the author of the book of Revelation. Now the question before us is when was Revelation written and where was it written?
Location and Date of Revelation – The Internal Evidence
There is both internal and external evidence that reveals that the apostle John wrote the book of Revelation while he was imprisoned on the Island of Patmos. The place where the apostle John wrote the book of Revelation is actually stated within the book itself. In Revelation 1:9 John states that he was on the Isle of Patmos,
I, John, your brother and fellow partaker in the tribulation and kingdom and perseverance which are in Jesus, was on the island called Patmos because of the word of God and the testimony of Jesus. Rev. 1:9 (NASB)
It is important to note that he says he had been persecuted for the faith – “partaker in the tribulation” and “perseverance, which are in Jesus.” Then he adds “because.” The Greek word translated as “because” is dia, which means “on account of, for the sake of, for this reason.” That is, he had suffered for the Word of God and the testimony of Jesus.
Location and Date of Revelation – The External Evidence
This external evidence supports the internal evidence that the apostle wrote the book of Revelation while he was imprisoned on the Island of Patmos.
The external evidence confirms that Christians were imprisoned during the time of Domitian. The evidence agrees with Revelation 1:9. Persecution of Christians reached a peak during Emperor Domitian’s reign (A.D. 81-96).
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.” (Pliny Natural History 4.69-70; Tacitus Annals 4.30)
Patmos had a long history of being a Roman prison. Even in A.D. 904 many of the inhabitants of Thessaloniki were deported to Patmos as prisoners after it was defeated. Knowing that the Romans used the Island of Patmos as a prison strongly suggests that is why John was there.
Clement of Alexandria (A.D. 150 – 215) confirms that John had been on the Island of Patmos.
And that you may be still more confident, that repenting this truly there remains for you a sure hope of salvation, listen to a tale, which is not a tale but a narrative, handed down and committed to the custody of memory, about the Apostle John. For when, on the tyrant’s death, he returned to Ephesus from the Isle of Patmos . . .
Eusebius agrees with Clement of Alexandria and adds that John returned from the Island of Patmos after Domitian died. He also states that Domitian reigned after Nero. Historical records indicate that Nero reigned from A.D. 54 to A.D. 68 and Domitian reigned from A.D. 81 to A.D. 96. Notice that in the following quote Eusebius states that “to do the same thing that the latter did” refers to Nero. Further, in the following quote Eusebius refers to Nerva as Domitian’s successor. Historical records indicate that Nerva reigned from A.D. 96 to A.D. 98. This provides conclusive evidence that the Domitian Eusebius refers to is the Domitian who reigned from A.D. 81 to A.D. 96.
Tertullian also has mentioned Domitian in the following words: Domitian also, who possessed a share of Nero’s cruelty, attempted once to do the same thing that the latter did. But because he had, I suppose, some intelligence, he very soon ceased, and even recalled those whom he had banished. But after Domitian had reigned fifteen years, and Nerva had succeeded to the empire, the Roman Senate, according to the writers that record the history of those days, voted that Domitian’s honors should be cancelled, and that those who had been unjustly banished should return to their homes and have their property restored to them. It was at this time that the apostle John returned from his banishment in the island and took up his abode at Ephesus, according to an ancient Christian tradition.
Irenaeus adds that John lived in Ephesus after leaving the Island of Patmos. He remained there until Trajan began his rule.
Then, again, the Church in Ephesus, founded by Paul, and having John remaining among them permanently until the times of Trajan, is a true witness of the tradition of the apostles.
Trajan reigned from A.D. 98 to A.D. 117. This confirms the internal evidence of the book of Revelation regarding the place where John wrote Revelation. Since Domitian began his reign as Caesar in A.D. 81 and died in A.D. 96 and John was released from Patmos after Domitian died, this indicates Revelation was written around A.D. 95-96.
There are some who argue that Domitian was actually Nero because they argue for an earlier date for the writing of the book of Revelation. But it should be noted that Eusebius uses the phrase “age of Nero and Domitian” in his book called “The Church History” book III, chapter XXXII. He clearly refers to two separate individuals in the phrase. Those who claim that Nero and Domitian were interchangeable names for the same person have ignored the obvious.
The John MacArthur Bible Handbook states the following about the date of Revelation.
Revelation was written in the last decade of the first century (ca. A.D. 94-96), near the end of Emperor Domitian’s reign (A.D. 81-96). Although some date it during Nero’s reign (A.D. 54-68), their arguments are unconvincing and conflict with the view of the early church. Writing in the second century, Irenaeus declared that Revelation had been written toward the end of Domitian’s reign. Later writers, such as Clement of Alexandria, Origen, Victorinus (who wrote one of the earliest commentaries on Revelation), Eusebius and Jerome affirm the Domitian date.
The spiritual decline of the the seven churches (chaps. 2,3) also argues for the later date. Those churches were strong and spiritually healthy in the mid-60s, when Paul last ministered in Asia Minor. The brief time between Paul’s ministry there and the end of Nero’s reign was too short for such a decline to have occurred. The longer time gap also explains the rise of the heretical sect known as the Nicolaitans (2:6, 15), who are not mentioned in Paul’s letters, not even to one or more of these same churches (Ephesians). Finally, dating Revelation during Nero’s reign does not allow time for John’s ministry in Asia Minor to reach the point at which the authorities would have felt the need to exile him.
Since the early church fathers had already concluded that 1) the Apostle John was the author of Revelation, 2) the book of Revelation was written near the end of Domitian’s reign, and 3) that the book was written while John was on the Island of Patmos, we can conclude that Augustine of Hippo (A.D. 354 – 430) had no influence on the authorship, dating, or John’s location while writing the book. It is important to note that Augustine lived hundreds of years after these conclusions had already been reached. We can also conclude that John was imprisoned on the Island of Patmos. That is the testimony of both the internal and external evidence.
1. Irenaeus. Against Heresies. 4.20.11. Ante-Nicene Fathers. Hendrickson. 1995. vol. 1, p. 491.
2. Irenaeus. Against Heresies. 4.14.2; 4.17.6; 4.18.6; 4.21.3; 5.28.2; 5.34.2. Ante-Nicene Fathers. Hendrickson. 1995. vol. 1, p. 479, 484, 486, 493, 557, 564.
3. Justin Martyr. Dialogue With Trypho. 81. Ante-Nicene Fathers. Hendrickson. 1995. vol. 1, p.240.
4. John F. Walvoord. The Revelation of Jesus Christ. Moody Press. 1966. p. 12.
5. Geisler and Nix. A General Introduction To The Bible. Moody Press. 1973. pp. 187, 191, 193.
6. F. F. Bruce. The Canon of Scripture. InterVarsity Press. 1988. pp. 159-161.
7. Achtemeir et al. “Patmos” Harper’s Bible Dictionary. 1985. p. 755.
8. Clement of Alexandria. “Who Is The Rich Man?” XLII, Ante-Nicene Fathers. II, p. 603.
9. Eusebius. “Ecclesiastical History. III, XX, The Fathers of the Church. Hendrickson. 1995. I, p 149.
10. Irenaeus. “Against Heresies.” 3. 4, Ante-Nicene Fathers. I, p. 416.
11. Ibid. Eusebius. III, XXXII, p 163.
12. John MacArthur,. The MacArthur Bible Handbook. Thomas Nelson Publishers. 2003. p. 517.
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