The Book of the Sacred Magic of Abramelin the Mage

Thou shalt in no way use this Sacred Science to offend the Gret God, and to work ill unto thy neighbor; thou shalt communicate it unto no living person whom dost not thoroughly know by long practice and conversation, examining well whether such a person really intendeth to work for the good or for the evil. And if thou shalt wish to grant it unto him, thou shalt well observe and punctually, the same fashion and manner, which I have made use of with thee, and if thou doest otherwise, he who shall receive it shall draw no fruit therefrom.