Excerpt from The Shambhala Guide to Yoga by Georg Feuerstein.
In order to gain the unsurpassable bliss of the Self, the yogin willingly adopts a life of strict discipline. The aspirant begins by carefully regulating his or her moral behavior. This forms the bedrock of all types of Yoga. Reduced to its bare bones, yogic morality is the recognition of the universal Self in all other beings. The various moral rules expounded in the Yoga scriptures are a symbolic bow to the Self within the other person. Thus Yoga morality is inseparable from Yoga metaphysics. In their moral conduct, the yogins aspire to preserve the moral order of the cosmos within the limited orbit of their personal existence. In other words, they seek to uphold the ideals of harmony and balance. This endeavor is by no means unique to Yoga. Rather the moral code followed by its practitioners is universal and can be found in all the great religious traditions of the world.
As the American social critic Theodore Roszak correctly understood, the yogin’s first step must necessarily be a moral one:
“[H]igher consciousness is born out of conscience. ‘Consciousness’/'conscience’: the very words are related, reminding us that we cannot expect to expand spiritual awareness unless we also expand our moral awareness of right and wrong, good and evil. Later perhaps there will be ecstatic harmonies beyond the description of words in which the good and the evil of the world will be revealed as, mysteriously, the two hands of God. But only the soul that has honestly cast out violence, greed, and deception may begin the ascent to that lofty vision…
“Surely too many Western practitioners of yoga are playing trivial games with the psychic and physiological spin-off of the divine science. They learn to clearn their sinuses, to mitigate their migraine, to flirt with the joys of the kundalini. Perhaps, besides achieving an enviable muscle tone, they even happen upon occasional intimations of samadhi. But all these achievements become barbarous trifles if we forget that yoga, like all spiritual culture, is a life discipline and a moral wisdom.”