The only thing you're saying is that they may accept one book or religion over the other, and they are justified or condemned if it is right or wrong.
WHAT??? How is THAT an accurate system for determining the truth of one religion over another? Simply choose a book, and believe it is the word of God, and one day you'll either live in paradise, or burn in hell.
You MAY be violating the law if you do such-and-such action, but proponents will assure that it is perfectly legal, while opponents say the exact opposite. Just commit the act, and if you're punished for it, then you'll know for certain it was against the law. Of course, by that time it'll be too late.
Simple, but stupid.