Some Upanishads are written in verse, and others in prose and some are mixed prose and verse. The language, which is the Vedic rather than the classical style of Sanskrit, is sometimes obscure, but more often it is very straight and direct. As you read the texts you feel an atmosphere of sunlight, of open spaces, of the frankness, the innocence, and the purity of childhood. You feel that the people who dwelt upon these thoughts and experiences and gave expression to them were sturdy men, strong men, but not violent. (Violent people are weak; truly strong people are gentle, pure, and innocent, and their gentleness is not associated with any kind of weakness.) You also feel that there was not much restriction in their life. By that I do not mean there was licence, but that there was no rigidity about them, and you feel that you would rather like to go back to those people; you cannot escape the feeling that they represented the highest expression of life on earth; that they were highly civilized and highly cultured.
The life they lived, these people who taught the Upanishads, was a very simple life, mostly. But sometimes these teachings were originally given by kings who lived in the luxury of a palace. There is a theory, which Swami Vivekananda himself held to some extent, that the Vedanta, or the Upanishads, really originated among the ksatriyas, the warrior caste, rather than among the brahmins. And in support of this we often find in the history of India that the most liberalizing thoughts in religion or philosophy came not from the first caste, not from the brahmins, but from the second caste, the ksatriyas. For example, Sri Krishna was not a brahmin-, he was the son of a ksatriya, and Buddha, who democratized the teachings of the Vedanta and spread them broadcast, was the son of a ksatriya king. We do not consider this to be a reflection on the brahmins, we say that just as two opposite forces create a balance, so in every community or every system of knowledge there have to be two forces working one conservative and the other liberal. If liberalism has complete freedom in its own experimentation, it is apt to kill itself; therefore, there has to be a conservative force that will challenge it. When liberalism can stand that challenge it is gradually embodied into the accepted authority. In India the brahmins have represented that conservative force, and in the matter of Vedanta we find that some of the teachers were brahmins, others were ksatriyas. So we sometimes find brahmins going to ksatriyas to learn this most excellent truth, the truth about the Atman and Brahman.
Well, whatever that might be, most of these teachers lived a simple life in an asrama, which can be translated as retreat. Just as modern retreats are located outside the cities in a solitary place in the midst of nature, so in those olden days there were many such retreats or hermitages all over the country, particularly in the Himalayan region. And many of these teachers who were generally called rsis, which literally means seers, because they directly perceived supernatural truths were established in these asramas and were supported by the rich or by kings, who considered it their duty to protect them and to supply their needs.
Those needs were very simple. They lived in huts; they would get up at what they called the brahma-muhurta, the hour of God, an hour before dawn, and would go in the dark or semidark to a nearby stream and bathe; then they would sit around a fire, which was always burning, but which at that time was burning brighter because the disciples had put more logs on it, and they would plunge into meditation. After long meditation some teachings would be given, and then they would all go to their respective duties. Later, classes would be held in the different branches of learning, particularly in the Vedas and the Upanishads; the rsis would teach their pupils the art of meditation; they would teach them what is called brahma-vidya the science of Brahman, or the science of God-realization, and they would teach them philosophy, so that their intellect would be trained in accordance with their spiritual findings. There were also other teachings, sometimes called vedahgas, which were essentially secular subjects like astronomy, prosody, grammar, and so on. The pupils themselves had to live a life of utmost asceticism, of which the most essential condition was the practice of celibacy. Many rules are given in the old books for this rigorous life. The pupils would live many years with the teachers, whose examples were considered very important as a part of their training. Then some of them would return to the world, get married, and live as ideal citizens. They would not give up their spiritual practices; rather, they would carry them on, and when they were fifty years old they were supposed to retire from the world and plunge again into a life of contemplation and meditation. And then, after some time, they would embrace the life of utter renunciation and become sannyasins, or wandering monks. That was the general picture.
It goes without saying that although there might have been hundreds and hundreds of such hermitages, not all the rsis were equally proficient. It is but natural that there were differences among them, and you find that some became very well known as great spiritual teachers and as great scholars of the Vedas or Vedanta. Of course, more people would come to them than to others, and one to whom thousands and thousands of people would flock used to be called kula-pati, the chief of the clan, the clan of spiritual aspirants. Such chiefs’ were very highly regarded, and necessarily used to receive great respect from all. And of course the kings and the nobles of a kingdom considered it their special duty to support them.