I have found something to be quite helpful (and safe as well) when determining whether or not I should read a certain book. Following the principle of the scorpion’s sting being in its tail, I check the end of the book first. That is where you will most likely find false doctrine (at least in its most recognizable and developed form). Many such books will sound very good, very pious and very safe in the first chapter. Error is then gradually presented in a manner which is hard to discern. (Remember, Satan is an angel of light.) By the end of the book the error has been fully developed and the poisonous sting has wounded the heart and conscience of the reader. So check the end to see what the conclusion is first, before deciding to read the whole.
K. Heslop (adapted from the YP Forum)