IsaacHDXxx form2Isaac RebirthKeeper sprite

A gray book with an inverted pentagram on its cover.


Upon activation, blood will run from Isaac's (now empty) eye sockets, and will also have a red Cross of St. Peter on his forehead. This adds 2 points of Damage for the current room.

In addition to its +2 base damage modifier, if Isaac holds Blood Of The Martyr (without also having Max's Head or Magic Mushroom), the book gives a 1.5x damage multiplier.

Increases the chance of a Devil Room spawning by 25%.


  • Judas starts the game with this item.




  • In the Dead Sea Scrolls, (not to be confused with the item of the same name) Belial is the leader of the Sons of Darkness.
  • During development, there was an item known as Satanic Bible. It later evolved into the Book Of Belial.
    • The Book of Belial is the third book of The Satanic Bible, and describes magic rituals.
  • XV The Devil shares its effect with this item and does not stack with the Book of Belial.
  • The upside down pentagram on the book is a widely known satanic ritual symbol.

Start a Discussion Discussions about The Book of Belial

  • Exactly how does Book of Belial help devil rooms?

    2 messages
    • There seems to be some disagreement between some articles on this. The beggar page states that activating the book is what gives the +25% cha...
    • Revelations is just a soul heart. As for the book of Belial, why NOT bring it to the Boss Room. It's a free damage up.
  • Stacks with Self?

    8 messages
    • Not to mention the fact that the BoB page says it stacks with itself. In quest to test this, I invoked the power of Cheatengine inf item power,...
    • Tested with spider mod, does not stack

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.