The Aitareya Upanishad belongs to the Rig Veda and the Upanishad proper consists of three chapters. This is part of the Aitareya Aranyaka, and the Upanishad begins with the Fourth chapter of the second Aranyaka, and comprises Chapter IV, V and VI. The preceding parts deal with sacrificial ceremonies like mahavrata and their interpretations.
It is the purpose of this Upanishad to lead the mind of the sacrificer away from the outer ceremonial to its inner meaning. All true sacrifice is inward. Sankara points out that there are three classes of men who wish to acquire wisdom. The highest consists of those who have turned away from the world, whose minds are free and collected, who are eager for freedom. For these the Upanishad (Aitareya Aranyaka II. 4-6) is intended. Others wish to become free gradually by attaining to the world of Hiranya-garbha. For them the knowledge and worship of the prana, life-breath is intended. (Aitareya Aranyaka II 1-3). There are still others who care only for worldly possessions. For them the meditative worship of Samhita is intended.
The Taittiriya Upanishad belongs to the Taittiriya School of the Yajur Veda. It is divided into three sections called Vallis. The first is the Siksa Valli. Siksa is the first of the six Vedangas (limbs or auxiliaries of the Veda); it is the science of phonetics and pronunciation. The second is the Brahmananda Valli and the third is the Bhrugu Valli. These two deal with the knowledge of the Supreme Self, paramatma-jnana.
Katha Upanishad, also called Kathakopanishad, which belongs to the Taittiriya School of the Yajur Veda, uses the setting of a story found in ancient Sanskrit literature (1). A poor and pious Brahmana, Vajasravasa, performs a sacrifice and gives as presents the priests a few old and feeble cows. His son, Naciketas, feeling disturbed by the unreality of his father's observance of the sacrifice, proposes that he himself may be offered as offering (daksina) to a priest. When he persisted in his request, his father in rage said, 'Unto Yama, I give thee.' Naciketas gives to the abode of Yama and finding him absent, waits there for three days and nights unfed. Yama on his return offers three gifts in recompense for the delay and discomfort caused to Naciketas. For the first, Naciketas asked, 'Let me return alive to my father.' For the second, 'Tell me how my good works (ista-purta) may not be exhausted'; and for the third, 'Tell me the way to conquer re-death (punar mrtyu).'
In the Upanishad, the third request is one for enlightenment on the 'great transition���, which is called death.
The Upanishad consists of two chapters, each of which has three Vallis or sections.
There are some passages common to the Gita and Katha Upanishad.
(1) Taittiriya Brahmana: The first mention of the story is in the Rig Veda where we read how the boy Naciketas was sent by his father to Yama (Death), but was allowed to get back on account of his great faith, sraddha.
The Prasna Upanishad belongs to the Atharva Veda and has six sections dealing with six questions put to a sage by his disciples who were intent on knowing the nature of the ultimate cause, the power of Aum, the relation of the Supreme to the constituents of the world. The Upanishad is so called as it deals with prasna or question.
The Kena Upanishad derives its name from the first word Kena, by whom, and belongs to the Sama Veda. It is also known as the Talavakara, the name of the Brahmana of the Sama Veda to which the Upanishad belongs.
It has four sections, the first two in verse and the other two in prose. The metrical portion deals with the Supreme Unqualified Brahman, the absolute principle underlying the world of phenomenon and the prose part of the Upanishad deals with the Supreme as God, Isvara. The knowledge of the Absolute, para vidya, which secures immediate liberation (sadyo-mukti), is possible only for those who are able to withdraw their thoughts from worldly objects and concentrate on the ultimate fact of the universe. The knowledge of Isvara, apara vidya, puts one on the pathway that leads to deliverance eventually (karma-mukti). The worshipping soul gradually acquires the higher wisdom, which results in the consciousness of the identity with the Supreme.
The Mundaka Upanishad belongs to the Atharva Veda and has three chapters, each of which has two sections. The name is derived from the root mund, 'to shave,' as he that comprehends the teaching of the Upanishad is shaved or liberated from error and ignorance. The Upanishad states clearly the distinction between the higher knowledge of the Supreme Brahman and the lower knowledge of the empirical world. It is by this higher wisdom and not by sacrifices or worship, which one can reach Brahman. Only sanyasi, who has given up everything, can obtain the highest knowledge.
The Mandukya Upanishad belongs to the Atharva Veda and contains twelve verses. It is an exposition of the principle of Aum as consisting of three elements, a, u, m, which refer to the three states of walking, dream and dreamless sleep. The Supreme Self is manifested in the universe in its gross, subtle and causal aspects. Answering to the four states of consciousness, wakefulness, dream, dreamless sleep, transcendental consciousness (1) these are aspects of the Godhead, the last alone being all-inclusive and ultimately real. The Absolute of mystic consciousness is the reality of the God of religion. The Upanishad by itself, it is said, is enough to lead one to liberation. (2)
Not only by the simple reading of the Upanishads can one become great in spiritual life. We should try at least to adopt only one principle of any of the Upanishads. By that practice, we can lead a highly spiritual life. The spiritual life leads us to have a comfortable living without any frictions. I thank Almighty and Swamiji for giving me the opportunity to share my thoughts on Spirituality. In the next issue, I will meet you all with some more Spiritual thoughts of our ancient Rishis and Saints.