The first requirement of spiritual development is self-discipline. In man the little devil and the even smaller angel get along perfectly well side by side, and our weaker self often prevails over our better self. Therefore, before the beast that dwells in man is tamed, it is idle to speak of finer, purer ideals. Through spiritual practices one must be cleansed of hindrances, and then the teaching takes root more firmly. Some believe that listening to the sacred message depends on no prior requirement at all, and yet we may say that experience shows progress to be surer when man keeps to clear moral requirements. The first steps of yoga, too, lay down moral prohibitions and recommendations: what is best avoided and what is best practised for the sake of development. We may speak of three levels of discipline: in bodily existence, in speech and in thought. Man can discipline his body with a readiness to serve and by following moral principles, his words with truth, and his thoughts with inner purity and composure, with spiritual calm. Perhaps this comes closest to mastering the soul…
The soul is inherently feminine in nature, that is to say, even its own happiness serves the joy of others. For the spiritual aspirant, the body, the mind and the soul alike are as women, who must be cared for and whose good master he must become.
But what does it mean to be master of something? Exploitation and subjugation, or rather alliance and care? The question is rhetorical, for if we do not picture a serving ruler, then we can only be speaking of a ruling servant, and that is far from ideal. Only a false master does not value his good servant, and only a false servant does not value his good master.
On the face of it, there are two figures: the soul and its master. As long as 'soul' stands rather for man's psychological system, his world of feeling and his mental self, it is wiser to read the injunction as the control of intelligence. But if the soul is the true self, the eternal soul-spark that pervades the body with the miracle of being alive, then the soul and its master cannot really be separated, since man is in truth the soul itself, not the perishable body. In that case it is more accurate to read the injunction by reversing the order of its words while making their sense more precise, meaning that the soul should be the master of man's life. In plain words: Take care of your own spiritual salvation, your enlightened self-interest!
Elsewhere it is said that, for the sake of his spiritual development, man must take possession of his conscious self (read: he must become the master of his soul), then place this disciplined self in the service of God, that is, reintegrate into the higher sphere.
So many teachings, so many traits ascribed to the soul – from the unnameable to the crown of creation – yet we now choose one particular property, and that is desire. '… they say that man is made of desire. As is his desire, so is his will, as is his will, so is his deed, and whatever deed he performs, that is where he will arrive' – declares the secret teaching of the Great Forest (Brihadaranyaka Upanishad 4.4.5).
Desire is proper to the soul, the pledge of individual existence, and therefore desire must not be abolished but disciplined. Just as desire can bring about one's downfall, so it can also further liberation. Self-mastery, self-discipline, is in truth a liberation of energy. Controlled energy, once liberated, is put to good use. If we understand this within a personal spiritual relationship, then we may also speak of a transfer of energy, for though the master enjoys the energy of his disciples, this is still no one-way relationship, because the disciples receive their master's power. This is nothing other than empowerment, initiation, mystery and eternal secret, as master and disciple, the soul and its master, exist, each presupposing the other.