Yoga should be practised with firm determination and perseverance, without any mental reservation or doubts.
Bhagwad Gita 6.23 * I bow with my hands together to the eminent sage Patanjali, who removed the impurities of mind through yoga, of speech through grammar, and of body through medicine.
Bhoja's Rajamarttanda commentary on Yoga Sutras * You can enter yoga, or the path of yoga, only when you are totally frustrated with your own mind as it is. If you are still hoping that you can gain something through your mind, yoga is not for you.
Osho * Yoga teaches us to cure what need not be endured and endure what cannot be cured.
B K S Iyengar * The word yoga literally means to join up, or to yoke together. What we're trying to join together in yoga is body, mind and spirit.
Courtesy: Sacred Space, Times of India