PS. They are one of the purest I've found, although all spiritual paths are pure, the purity is mostly dependent on the intention of the one following them. Remember you can't be 100% pure on this plane, Earth is too polluted, you wouldn't be able to survive, unless you become a Saint or an Avatar. Trust me I've tried for many years. People try to take advantage of you. I don't know much, it's just my experience.
I've heard this was the words of Christ, but am not 100% sure, "be as innocent as a lamb but as cunning as a snake". We gotta survive somehow!