A text that is of high importance to a religion, normally one that is considered by believers to be by or about the deities involved in that religion. It is often considered a horrible thing to question the authenticity of that text around believers of that text.

See: Bible, Torah, Qur'an, Vedas, Book of Mormon, Dianetics

Just due to the number of them, some must be wrong. Why must we play russian roulette with the soul?