From SuspireWiki

The Book of Eschaton

• Our Working Version: The Book of Eschaton (working version)
• Basic Overview: Cryptic verses of prophecy foretold by Longinus.
• "Finally, Eschaton contains a number of prophecies spoken by Longinus to guide his descendants and prepare them for the judgment of God. Unfortunately, Longinus chose to mask his visions in cryptic verses that defy easy analysis, and Eschaton has produced more schisms than accurate predictions of historical events. However, many Sanctified scholars fervently point to specific passages of Eschaton to show that Longinus predicted everything from the rise of Charlemagne to the Protestant Reformation to the assassination of JFK. Eschaton is most important to the core body of Lancea Sanctum faith for its predictions regarding the ultimate fate of the Damned." (LS, pg. 52)
• Also, we know a bit about how it ends... "The final chapters of Eschaton suggest that a vampire who fulfills the role for which God has chosen her and survives until the End of Days may seek absolution for all her sins. If her contrition is genuine, God will grant her absolution, thereby proving that His Infinite Grace is available to even the most corrupt and debased creatures. The vampire, now truly Sanctified, will ascend to Heaven as a reward for her acceptance of the burden of vampirism. The book cautions, however, that absolution will not be available to those who deny their vampiric natures. Those who believe that Humanity can be retained through personal willpower alone are guilty of the sin of Pride and will not be welcomed into the Kingdom of Heaven." (LS, pg. 52)
• So, basically, you have to write a mystically-themed book full of prophecy that ends with a discussion on how Vampires can get into heaven.