Spiritual Yoga: The Path to Highest Pleasure
There's material yoga, and there's spiritual yoga. The material kind will make us feel more peaceful, limber, and healthly. The spiritual kind will teach us how to attain a state of ever-increasing transcendental pleasure.
In this book Srila Prabhupada teaches the path of spiritual yoga, Krishna consciousness, elaborating on the instructions a divine king named Rsabhadeva imparted to His sons long, long ago in India.