What are the things of the spirits?

Spirit-lives have possessions―things outside of themselves that can take shape, and be, but yet which if not rightly used will vanish away. 

The true and inner law of possession is more binding in the spirit world than with us—

I can have nothing unless I need it for myself―or for another, and I must use it―or it will leave me, vanishing away as though they had not been. 

Spirit-lives have the outward, as well as the inward, but they are always intimately related—the strength that is not used in highest service vanishes away and the outward beauty, which typifies that strength vanishes likewise.