This fourth observance is one which often makes people uncomfortable, as it seems on the surface to be tied in with moralizing and repression. However, what use is chastity or celibacy when the mind is tormented with desire. This would merely be self-torture, as dissipating an indulgence as sexual licentiousness. Two of the root causes of affliction common to us all are attraction, the product of desire, and aversion, the product of pain. The observance of continence calls upon us to moderate all our desires, be they sexual or otherwise.
Desire is, in itself, an unrealized potential that requires fulfillment in one of two ways. Either the desire will be satisfied or it will be thwarted. In the case of satisfaction the mind will want more. In the second case frustration will either urge us to further attempts at satisfaction, or it will feel the anguish of being denied. Whatever the outcome, the potential of desire leads to more anguish. Even if we are moderate by nature, many small desires fulfilled can lead to greater desires, and many small desires frustrated can lead to greater anguish. All of this uses up energy that is directed outwards towards the material world and leads us further away from the goal of being centered and at peace.
Actively stifling desire, either for another person or for some material object, is never the answer, however, lest it be stoked into full-blown obsession or infatuation. Or worse, the part of us that is able to experience delight begins to atrophy and life turns gray and joyless. The key, then, is the practice of dispassion. Rather than investing more and more energy into the contemplation and pursuit of our desires, we should attempt to withdraw energy, freeing it up for more important pursuits. The intent of continence is not to make life miserable, but to make it more varied and less obsessive, for the joys to be lighter, more numerous and less fraught.
Yoga in Action
The Great Vow of Yoga