Om Apyayantu mamangani vakpranascaksuh srotramatho balamindriyani ca sarvani; Sarvam brahmaupanisadam ma’ham brahma nirakuryam ma ma brahma nirakarodanirakaranamastvanirakaranam me’stu; Tadatmani nirate ya upanisatsu dharmaste mayi santu te mayi santu. Om Santih Santih Santih.

Om, the word Om is always used at the beginning and end of anything said or done; Mama, my; angani, organs; vak, the organ of speech; pranah, the organ of breathing; caksuh, the eyes; srotram, the ears; atho, and; balam, strength; ca, and; sarvani indriyani, all the organs; apyayantu, may be well nourished; sarvam, all things; aupanisadam brahma, are Brahman, the subject-matter of the Upanisads; aham ma, may I never; brahma nirakuryam, deny Brahman; brahma ma ma nirakrot, may Brahman never deny me; anirakaranam, no rejection; astu, may be [from Brahman-i.e., may Brahman never reject me]; me by me; anirakaratyam astu, may [Brahman] never be disowned [i.e., may I never feel that I am separate from Brahman]; upanisatsu, in the Upanisads; ye dharmah, those good things [that are spoken of]; te, they; tat-atmani nirate, which are said to be in the Self; mayi in me; santu, may they be; te mayi santu, may they be in me. Om santih, peace [relating to the body and mind]; santih, peace [relating to animals]; santih, peace [relating to the elements].

May all my limbs grow strong, so also my breath, speech, eyes, ears, and all my organs. All is Brahman, of which the Upanisads speak. May I never turn away from Brahman. May Brahman never turn me away. Let there be no turning away, no turning away at least on my side. I am engaged in the study of the Self. The Upanisads speak of qualities tim one must possess to succeed in such a study. Ma I acquire those qualities. Om Peace! Peace! Peace!

This is a prayer for strength. Why do we need strength We need strength so that we can understand Upanisad—so that we can understand Brahman, Truth, which is discussed in the Upanisad. I xv the Truth; I want the knowledge that is in the Upanisad. As the Mundaka Upanisad (III.ii.4) says, ‘Noyamatma balahinena labhyah—this knowledge is not by the weak:’ It is for those with strength—physical strength, intellectual strength, and moral strength. Upanisads are difficult and very subtle. The cannot understand Brahman. So this is a very significance prayer to begin the study of an Upanisad.

The Chandogya Upanisad is found in the Chandogya Brahmana of the Sama Veda. The Chandogya Brahmana lists ten chapters altogether, the last eight of which constitute the Upanisad The name of this Upanisad is derived from the word chandas. A person who sings the Sama Veda (chandas) is called a Chandoga. And the beliefs and practices of the Chandogas are set forth in the Chandogya Upanisad.

Each of the chapters of the Chandogya Upanisad Important the first five chapters are about worship and meditation (that is, they are dualistic); whereas the sixth chapter on, they are about Brahman (and in that sense they are more or less non-dualistic) the purpose of the meditation chapters is to emphasize the need for a pure heart. Only when the heart is pure can instructions about Brahman be effective.

The Chandogya Upanisad occupies a high place among extant Upanisads. Its language is simple and it many stories, but its is profound care of the needs of ordinary people as us those who are highly intellectual It is like a loving mother, leading her child by the hand.

The Upanisad begins by telling people what they have to do to maintain spiritual progress, and it offers tow options: either ritualistic worship as prescribed by the scriptures, or meditation on the sublime Brahman, again as prescribed by the scriptures. The Chandogya concedes that for most people the first option the best. They are people incapable of thinking of anything beyond the reach perception. Brahman, beyond thought and speech, means nothing to them. They have many desires and they would be happy to have those desires fulfilled. Ritualistic worship offers them the opportunity to attain just those things they desire.

But the Upanisad makes no secret of the fact that everything that ritualistic worship offers—money, health, beauty, power, even heaven—is short-lived. If a person wants permanent peace and happiness, he has to have liberation—liberation from the bondage desires. And this attainable only through Self-knowledge. As the Svetasvatara Upanisad (111.8) says: ‘Tameva viditva’timrtyumeti nanyah pantha vidyate’yanaya—if you know that [Brahman], you overcome death. There is no other way [for liberation].’ This is a warning to those who engage in ritualistic worship, thinking, they will get everything they want through it. The Svetasvatara Upanisad says that the only way to attain permanent peace and happiness is through knowledge of Brahman—that through Self-knowledge.

The Chandogya Upanisad sounds the same warning, and having done this, it tries to draw our attention to Self-knowledge. As a first step in this direction, it gives an instruction on the udgitha, the recitation of Om. This is part of the worship a person has to perform to bring the mind under control. Though the goal is self-knowledge, a person must first control the mind by doing some upasana (spiritual practices). The Isa Upanisad (verse 11) also gives this advice. It asks a person to combine vidya (worship of gods and goddesses) and avidya (performing sacrifices.). This is the path of gradual liberation.

Sankara also recommends this for those who are not yet ready for the more difficult path of renunciation. In his commentary on the Chandogya Upanisad, he advises that they practice the udgitha, the recitation of Om. A sure way of controlling the mind is to recite Om whenever you do or say anything. To emphasize its importance, the Chandogya Upanisad devotes its first five chapters to the udgitha. From then on it discusses nothing but Brahman.

The Chandogya Upanisad was of ten quoted by Sankara in his commentaries to establish his philosophy of non-dualism. In fact, there is hardly any issue in Vedanta which is not discussed in the Chandogya. It is a complete manual on Vedanta.