[It] refers to a story about a man who lived in early China and who loved dragons, or at least images of dragons. In Asian mythology, dragons lived both in underwater palaces and dwelt in clouds with the power to cause rain, and they were considered a symbol of good fortune. This man had collected paintings and carvings of dragons which he had throughout his house. One day when a real dragon heard of the man’s love for dragons, he came to visit. But when the real dragon appeared, the man was terrified. Don’t be fooled into thinking that reading about Buddhism and fantasizing about Zen practice are enough – jump in and taste the truth for yourself through your own living practice. There is a saying in Zen, pictures of rice cakes cannot satisfy hunger.
http://www.intrex.net/chzg/pat42.htm