The Burning of Rome

Christ is said to have been crucified sometime around 33 AD, Rome was burned  in 64 AD, a mere 31 years. Christianity grew so quickly that it had spread from Israel to Rome, and had become so common that Nero was able to blame the burning of Rome on Christians, at a time when many of the people who were mentioned in the New Testament were still alive to question. These people were so convinced that Christianity was true, that they choose to die, rather than deny Christ. Even the disciples who knew for a FACT if Christianity was true or not were willing to die rather than reject Christ. Why would they endure painful deaths, if they could admit the truth, and go free?