Sri Aurobindo observes that people frequently try to start Yogic practice with Asana and Pranayama without observing the preliminary foundations set forth as requirements for the practice of Raja Yoga: “In modern India people attracted to Yoga, but picking up its processes from books or from persons only slightly acquainted with the matter, often plunge straight into Pranayama of Rajayoga, frequently with disastrous results. Only the very strong in spirit can afford to make mistakes in this path.”
The problems that arise are due to the influx of new powers and energies into a mental, vital and physical framework that is simply unprepared to deal with them, and thus, the practitioner can be easily thrown out of balance and aggrandize the ego, the desire-soul and the greed for powers distracts the seeker from the true higher goals with which he started.
Raja Yoga insists that the starting point is what are called “Yamas” and “Niyamas”. Sri Aurobindo describes them thus: “The first are rules of moral self-control in conduct such as truth-speaking, abstinence from injury or killing, from theft, etc.; but in reality these must be regarded as merely certain main indications of the general need of moral self-control and purity. Yama is, more largely, any self-discipline by which the rajasic egoism and its passions and desires in the human being are conquered and quieted into perfect cessation. The object is to create a moral calm, a void of the passions, and so prepare for the death of egoism in the rajasic human being. The Niyamas are equally a discipline of the mind by regular practices of which the highest is meditation on the divine Being, and their object is to create a sattwic calm, purity and preparation for concentration upon which the secure pursuance of the rest of the Yoga can be founded.”
There is a deeper occult significance to these practices and they are not simply preliminary, but necessary from the viewpoint of the actual focus of the path of Raja Yoga. One of the primary stages of Raja Yoga is the ability to view the “mind-stuff” (“chitta”) and to bring it to a state of absolute unmoving quiet, without waves. This is the basis for the ability to enter into states of meditation (dhyana), concentration (dharana) and Samadhi. Every sense impression creates such waves, and every feeling of desire or attraction, hatred or anger obviously creates large waves which overwhelm the mind’s foundation of calm in the practice. Thus, when new energies come into the being through the later practices of Pranayama, for instance, if there is not this solid basis of non-attachment, and the mind is still able to be thrown up in waves, the entire focus of the Raja Yoga is simply destroyed. From this viewpoint, Yama and Niyama, in the expanded sense described by Sri Aurobindo, are some of the most important aspects of the practice of this path of Yoga. Without them, success in this path is essentially impossible.
Sri Aurobindo, The Synthesis of Yoga, Part Two: The Yoga of Integral Knowledge, Chapter 28, Rajayoga, pp. 516-517