require a unique set of people and an atmosphere conducive to having those on the other side of life willing to come through and able to come to the Earthly plane to speak. The people must be in complete love and complete harmony with one another.
Those in the afterlife who endeavor to communicate in circles such as Leslie Flint's and David Thompsons' are doing so to try to help humanity evolve spiritually, just as they are helping souls on their side. They are not communicating to get messages to relatives or keep hold on the Earth. Many remark, in fact, that they have little interest in earth for their own lives because of the new focus their lives have and the wonderful nature of the afterlife compared to the dismal condition of the Earth.
As part of their effort to help humanity evolve, they have given instructions for medium groups and the Spiritualist church specifically.