Book of the Word
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The Book of the Word is a religious text of the Kobollian faith.
It contains information regarding the exodus of humanity from the motherworld of Humanity, Kobol, and stories regarding humanity upon that planet.
Adama finds it to be useful in his search for the lost Thirteenth Tribe and Earth. It aids the finding of Kobol, as it tells of an endless magnetic void and a lone star (Lost Planet of the Gods, Part II).
Note
The Book of the Word of the Original Series is comparable to the Sacred Scrolls in the Re-imagined Series as it, too, led Laura Roslin to assemble the pieces of the Pythian Prophesy needed to find the direction to Earth in the new series.