The Yoga Sutra does not just offer one way to achieve the goal of yoga; it has several actions we can perform. At the beginning of the second chapter of the Yoga Sutra we are introduced to one particular form of yoga called “Kriya Yoga.” Kriya means action, or in this case a ritualistic approach to yoga. It has only three steps: tapas, svadhyaya, and ishvara-pranidhana. Tapas is the dedicated effort or asceticism needed in order for our practice to bear fruit. Svadhyaya is the study of ourself, or self-study. This self-study includes knowing the scriptures and the practices recommended to help us achieve the goal of yoga. Ishvara-pranidhana is a giving up of all the fruits of our labor to a higher cause. It is surrendering to something bigger than our small self. 
These three steps of the Kriya Yoga are not physical. As described, anyone could undertake a complete yoga practice without doing a single asana. The Yoga Sutra offers the path of Kriya Yoga as one possible way to reach the goal of a still mind. This is a mental yoga; effort, or tapas, comes from a strong will. Tapas is an absolute requirement for success. Self-study is also essential and this comes from looking within, as well as looking without, for guidance. The last step, ishvara-pranidhana, is the one that may seem the most foreign to our Western minds: to act without regard for the results.
The Bhagavad-Gita, a small book buried in the midst of the epic poem of India, the Mahabharata, explains, with wonderful imagery, the reason for surrendering the fruits of all you do to a higher power. The Bhagavad-Gita contains the teachings of the Lord Krishna to his friend, the mighty warrior Arjuna. Krishna attempts to remove the delusions affecting Arjuna, and explains that Arjuna cannot do anything unless God wants it to be so. Do not feel pride when you accomplish something meritorious, for what have you really done? Do not feel depressed when things do not go according to your desire, for God’s desire is always greater. Your only duty is to take the action; leave the results in God’s hands. This is a hard lesson to grasp, and even harder to put into practice.
In our yoga practice, things may not always work out the way we hope. Some days we seem to be moving backward. But this is only a problem when we expect particular results. Give up the expectation and just do it. The will, the energy to do it, comes from tapas. Knowing what to do comes from self-study. The results are beyond your control. Offer them back to the source, or to anyone or anything else that may need assistance. Send the benefits of your effort to someone or something that needs special help right now. That is the power of prayer. That is the power of faith. Without faith, every spiritual practice flounders.
In Yin Yoga, the results may not be obvious for a long time. Yin tissues, such as our ligaments, have a lower blood supply to them than the yang tissues, such as our muscles. They don’t strengthen or lengthen as quickly as our muscles. Our range of motion may take a long time to increase, or may not grow at all. But in the end, that is not the real point of the practice. Yin Yoga will help us to be healthy, strong, focused, and open. But all this too, is not the ultimate point. The ultimate result is outside of our control. If we succeed in our practice, it is because of grace from elsewhere. Our job is to simply do the practice.
- — If you look back at the drawing of purusha and prakriti you may notice that there is one particularly large purusha shown. This larger purusha depicts ishvara: the first among equals. According to the Yoga Sutra, this is a special purusha – one that has never been tainted by prakriti. Ishvara is a lord, a particularly pure purusha, but not necessarily God. It is not clear in the Yoga Sutra whether this lord is the original creator of the universe or just the first among the many purushas. What is clear is that ishvara is not a personal god who will interfere in our personal life. However, ishvara does serve as an inspiration for us.