This is an excerpt from Lü Dongbin's The Secret of the Golden Flower, specifically Chapter 3, "Returning the Light and Guarding the Center." It details a meditative practice aimed at cultivating inner energy ("light") by reversing the natural outflow of consciousness through the eyes. The practice involves focusing on the tip of the nose to achieve stillness and then observing and releasing thoughts, integrating elements from Daoism, Buddhism, and Confucianism. The ultimate goal is enlightenment, achieved through a balance of concentration and wisdom. The text emphasizes the importance of consistent practice and understanding the true meaning of "reflective illumination."