This is Yoga
by Swami Sivananda
Yoga is an exact science. It is a perfect, practical system of self-culture. It is the discipline of the mind, senses and the physical body. It helps the student to attain perfect concentration of the mind, ethical perfection, moral excellence and spiritual calmness. It is the master-key to unlock the realms of Peace and Bliss, Mystery and Miracle.
Yoga does not consist in sitting cross-legged for six hours or stopping the beatings of the heart or getting oneself buried underneath the ground for a week or a month; these are mere physical feats. Real Yoga is the attainment of the highest divine knowledge through conscious communion with God. The word Yoga comes from the Sanskrit root "Yuj" which means "to join." Yoga is the science that teaches us the method of uniting the individual soul with the Supreme Soul, of merging the individual will in the Cosmic Will.
Yoga transmutes the unregenerate nature of the student and raises him to the highest state of Divine Glory and Splendour. It bestows on you increased energy, vitality, vigour, longevity and a high standard of health. It will infuse in you a sense of security, a new strength, confidence and self-reliance. Yoga brings a message of hope to the forlorn, joy to the depressed, strength to the weak, and knowledge to the ignorant. It kills all sorts of pain, misery and tribulation.
By practice of Yoga you can turn out efficient work within a short space of time, resist temptations, remove disturbing elements from the mind and attain full success in every walk of life. Through the practice of Yoga you can control the subtle forces within the body and command nature. You can unfold all your latent faculties and develop physical, mental, supernatural and divine powers. The whole mystery of Nature will become an open book to you. You can live in the Eternal Light and Glory of God.