The ancient Indian saints and sages were most advanced in their spiritual pursuit. They composed voluminous texts named 'Vedas' in order to describe their spiritual findings and realizations. The cream of Indian spiritualism is found in the Upanishads, which are the last volumes of Vedas. It is believed that Vedas were composed from 1500 BC onwards and Upanishads were composed from 700 BC onwards. Upanishads are not only for Hindus, but for the whole of mankind.
Out of eleven principal Upanishads, it is accepted that Isha Upanishad is the oldest of all. Let us see what this Upanishad describes in order to search for God.
- God resides in living beings. Isha Upanishad begins by describing that whatever living beings inhabit the world here, God resides in all of them. There are two things in the world -- on one hand is life and consciousness and on the other, inert matter. God does not reside in the inert and unconscious matter or material world. The material world appears to exist for God or a divine truth exists. But God resides in the living beings in the form of life and consciousness. The essence of a being is its life and consciousness. The source of life and consciousness in living beings is called self, soul or Atman. At death when Atman departs from the body, it remains behind as dead matter. Nothing can give new lease of life. So Atman is everything of a being and the home of God is Atman.
- A self-slayer is one who does not realize Atman. Isha Upanishad describes self-slayers as those who do not try to realize Atman as the home of God. As a consequence after their death, they enter into a world of blind darkness. So without spending time, men should try to realize God within.
- Turn away mind from outside. The consciousness of Atman is expressed and felt in the mind. The nature of mind is to move fast. Sometimes it moves, sometimes it is static; sometimes it is far away, sometimes it is very close. This mind is the heart of all. So in order to realize Atman, one has to turn away one's mind from the outside world and concentrate it on Atman.
- All souls are one. One who sees all beings in oneself and oneself in other beings comes to know everything. Nothing remains undisclosed for him. He becomes omniscient. All souls are one and the same. One should not see differences between beings or between self and God.
- Strike a balance between spiritualism and materialism - Isha Upanishad describes that those who worship false-knowledge (avidya) enter into darkness. In spiritual language, knowledge (vidya) means know-how about things which exist. In the world, only life and consciousness exist. So knowledge means know-how about life, consciousness, soul and God. Conversely false-knowledge is the know-how about things which do not exist. Material world and worldly objects in reality do not exist. Knowledge indicates spiritualism, and false-knowledge indicates material science.
Upanishad further describes that by knowing the futility of false-knowledge, you can overcomes death, and by realizing knowledge, you get immortality. Death is equal to matter. So by turning away from the material world, you overcome death and get immortality. Since you have material body, you cannot turn away from the material world completely. So you have to strike a balance between the material world and life or between science and spiritualism. Progress on science and spiritualism should go hand in hand. Otherwise civilization shall be destroyed.