How do you tune in with spiritual matter?

When you come into contact with an invisible or spiritual body, you are thrilled by the spiritual sense of touch, and every cell of your physical brain begins to vibrate with increased rapidity. And sometimes, when you possess a very finely adjusted physical intellect, this organ reaches a rate of vibration that is in tune with spiritual matter, and you enter into harmonious rapport and communication with the spiritual world, or with such life from that plane, as happens to be keyed to the same rate of vibration, as that to which you have attained.

Fragments of Spiritual Knowledge Pertaining to the Spiritual World