Any medium who lets himself be possessed at times by lying and malignant spirits in his séances would be fortunate to escape with his sanity and peace of mind. He should first learn how to protect himself before he opens himself up to outside and unseen powers. But such protection can be gained only by developing his own strength, character, knowledge, and aspiration. Indeed his personal spiritual growth calls for this passage to a higher stage. But this can be reached only by abandoning mediumship, at least for a time. At some future date, he might be able to resume it, but it would then be so vastly superior and so fully within his control that it would really be mysticism. For the controlling entity would be either his own higher self or a genuine living master.
-- Notebooks Category 16: The Sensitives > Chapter 13 : The Occult > # 127
