The Sibylline Oracles predict the time of Antichrist will arrive when “the limit of the time of the Phenix” comes around (Sib Orc 8:184, http://www.sacred-texts.com/cla/sib/sib10.htm). The complete number (“limit”) of the firebird is 7. The first century Roman historian Tacitus reported the 4th Phoenix/Firebird appeared in the days of Tiberius in AD 34 (Annal., vi, 28). The story of the firebird is this: The firebirds live 500 years and then they return to Egypt, hatch another bird and die. The young bird burns his father to ashes, and then rises from the ashes and flies away, not to be seen again for 500 years.
I know the firebird sounds crazy, and Tacitus, being the careful historian that he was, felt the same way. In Tacitus’ account of the phoenix he is apologetic for even mentioning it, but he says that he does so because he heard it from so many ancient sources including intellectuals in both Egypt and Greece, and he included it for completeness. Apparently, it caused quite a stir in Egypt because it was so extremely unusual and was witnessed by so many people. The return of the firebird was very obvious because the firebird came “with a multitude of companion birds marveling at the novelty of the appearance” (http://classics.mit.edu/Tacitus/annals.6.vi.html).
Tacitus’ report of the 4th phoenix gives a firm date with which to do computations for the origin of the firebird. Tracing the firebirds backwards (assuming the 3rd one ended and the 4th one began in AD 34), then the first one began in 1466, coincidentally with the time that Israel began its trek to the Promised Land. A sheer speculation could surmise that the first firebird began by rising from the ashes on Mt Sinai (Dt 4:11).
Based on the Tacitus observation of the 4th firebird, we can also compute the end of the firebird. If the 4th firebird started in AD 34, then the 5th firebird started in 534, the 6th in 1034, and the 7th in 1534. The limit of the 7th and last firebird will be at the end of its 500th year in 2034. When the 7th firebird reaches its limit, the Sibyls say the Antichrist/Beast will destroy Rome. That is about 3 years before the end of the world.
There is a compelling correspondance with an end of the world computed based on an AD 33 date for Jesus’ resurrection and the death of the last firebird. Jesus’ resurrection was 4, one-thousand-year days from creation. Like the physical creation took 6, 24-hour days to create, Barnabas says the world will only last 6 of these one-thousand-year days until the Lord brings all things to an end (Barnabas 15:4, http://earlychristianwritings.com/text/barnabas-lightfoot.html). The end of the 6th day is around 2033, depending on exactly the year in which Jesus was crucified.
Before the Antichrist burns Rome (Rev 17-18) at the return of the last firebird, there are to be a series of four plagues that preceed it (Rev 8:1-13). The second of these plagues is where a “great mountain burning with fire” is cast into the sea. Sure enough, an asteroid, Apophis, appears to be on a collision course with the earth in 2029 (http://www.guardian.co.uk/science/2005/dec/07/spaceexploration.research). Looks like it’s all coming together for an end of the 6th day.