Question: Why do flowers and the burning of incense help to bring good spirits back?Sri Chinmoy: It allows them to stay peacefully. It purifies the atmosphere. It is their food; it is a kind of fruit to them. You torture the spirits if your room is not clean when you invoke them, even though your body and your mind may be clean. You may be thinking of God and you feel you are pure, but if your room is not pure, it is torture for the spirits.
Sri Chinmoy, Astrology, the supernatural and the Beyond, Agni Press, 1973