How does the desire for knowledge come?

To the pure all things are pure. This saying means that the pure receive only that which is pure, for if an impure answer should flow into the mind, that mind itself is impure, and receives its own, and the answer of the pure spirit is not taken in and assimilated. 

When you thus question, receive no answer, but the highest and purest that your mind is capable of holding, and all will be well. Do not call on any spirit who is beneath yourself in love and wisdom—always on those above you. 

A father—or mother in spirit life will not reply falsely to a child left on earth. 

That father—or mother desires only the welfare of the child, and it is a great incentive to most fathers and mothers who have children on earth to progress in wisdom as rapidly as possible that they may be able to give it to loved ones there.

—Herr Franz in Spirit