Master Xu Yun is the founder of this lineage. He transmitted the Caodong Ch’an lineage to a layperson through the letter writing tradition and I transmit the dharma in the same way. Xu Yun lived for 120 years and he just traveled around teaching, building temples, and transmitting the Dharma. They called him Empty Cloud because he traveled from place to place like a cloud. And he manifested his empty self nature. It’s said by those who met him that his enlightenment was obvious, that he had no attachment to himself. He went around just being in a way that few others can.
To me it has a deeper meaning too. We are all empty clouds. We are all just floating around. We think we’re independent and permanent, but ultimately we have no self to hold onto, just like a cloud.