The following points are evidences from within the Book of Revelation itself that confirm the early date of its writing:
(1) The time statements of the book refer to soon events of cataclysmic Jewish importance. If it was written in 96 AD, there are no events soon from that time that could even remotely fit. If, however, it was before 70 AD, then the destruction of Jerusalem rises to the occasion as both Jewish and cataclysmic. The time statements demand we look here, and there is no historic support for a persecution of the Church under Domitian in the 90s.
(2) According to the epistles to the churches, the Judaizers were persecuting the churches (Revelation 2:9; 3:9). This assigns the book to the pre-AD 70 era, for the Jewish persecution of the Church dissolved at AD 70.
(3) The temple and the city were apparently still standing in Revelation chapter 11. John is sent to measure the city and temple, and Jerusalem is said to be under siege at the time of writing. It would not be possible for John to speak of these as still standing after 70 AD, for they were utterly destroyed at that date. And, if John is referring to some rebuilt temple in the far distant future, and he is writing in 96 AD, then his complete silence about the destruction of the temple and city in 70 AD is deafening--the destruction of Jerusalem is perhaps the greatest disaster in antiquity, and surely the greatest disaster in Israel's history. To imagine St. John overlooking the apocalyptic destruction of Jerusalem and the Temple while he discusses both as if they were still standing, is impossible. Rather, St. John is prophesing their impending doom just two or three years before they were made utterly desolate.
(4) There were "other apostles" still around according to Revelation 2:2. Tradition has it that all the apostles were dead before 70 AD and John was the only original possibly surviving past that time.
(5) Caesar Nero's name in Hebrew gematria adds up to 666. Since this was written about soon events, no other person can be found within this time scope whose name fits this requirement and description. For certain, none can be found in the soon future of 96 AD.
(6) Almost all scholars believe Revelation is inextricably linked directly to the Olivet Discourse. Since the best commentaries on the Olivet Discourse demonstrate that it is speaking of the events leading up to AD 70, so must Revelation be speaking of these same events.
(7) The 6th king in Revelation 17 is the one that persecutes the saints. The Roman emperors as listed by Josephus and Tacitus are as follows: (1) Julius, (2) Augustus, (3) Tiberius, (4) Caligula, (5) Claudius, then (6) Nero. Nero was the first and only Roman Caesar of the Julian line to persecute Christians. Nero's death ended the Julian dynasty. The one ruling after him reigned only a little while--Galba, for 6 months. If the 6th king is indeed Nero, he would be the one that "now is" according to the prophecy, and this would date the writing before 68 AD when Nero supposedly committed suicide. Nero also persecuted Christians for 42 months as is stated in the prophecy.