If there is no desire, it’s very difficult to portray that feeling in terms of visual art. People have great difficulty portraying the Buddha, because he doesn’t do anything. He just sits there. Bodhisattvas, the people who out of compassion took vows to save all sentient beings, are easier to portray. They tend to have a benevolent look, very gentle and soft. They show sorrow and pain because they realize that their fellow sentient beings are in pain and they want to save them.
From “Back to Square One,” in True Perception: The Path of Dharma Art, page 143