Final answer:
The error in the argument is that it assumes what it is trying to prove, making it a circular reasoning fallacy.
Step-by-step explanation:
The error in the argument is that it assumes what it is trying to prove, making it a circular reasoning fallacy. In order to accept the conclusion that there is a deity, the argument assumes that the book is from God and is truthful and accurate. However, this assumption is needed to accept the conclusion, which is a logical mistake.