"While having is based on some thing that is diminished by use, being grows by practice. (The "burning bush" that is not consumed is the biblical symbol for this paradox.) The powers of reason, of love, of artistic and intellectual creation, all essential powers grow through the process of being expressed. What is spent is not lost, but on the contrary, what is kept is lost. The only threat to my security in being lies in myself: in lack of faith in life and in my productive powers; in regressive tendencies; in inner laziness and in the willingness to have others take over my life. But these dangers are not inherent in being, as the danger of losing is inherent in having."
Erich Fromm. 1976. To Have or To Be. p.102. Harper & Row, NY