Chandogya Upanishad is one of the oldest Upanishads written on the Vedic Brahmana period about ninth to eighth century BC. Chandogya Upanishad is associated with Sama Veda. It is the part of Chandogya Brahaman that contains eight chapters. Chapter Seven of Chandogya Upanishad has been divided into twenty six khandas.

1st Khanda
The 1st khanda states about the dialogue between Narada and Sanatkumara. Narada approached Sanatkumara and requested him to teach him about the real Self or the Supreme Brahman.

2nd Khanda
The 2nd khanda deals with speech as Brahman. It states that speech is greater than a name. It helps one to recognise the Rig Veda, the Yajur Veda, the Sama Veda and the Atharva Veda. It also helps to understand about the epics and the ancient lore, the Vedas, the numbers, Brahma Vidya, the science of etymology, logic, time, ethics, the science of elemental spirits, the science of weapons, the science of serpents, fine arts, heaven, earth, water, fire, air, akasa, birds, trees, herbs, men, gods, righteousness and unrighteousness, truth and false, the pleasant and the unpleasant, the good and the bad etc. One who is aware of this and who meditates on the speech as Brahman would reach a long distance.

3rd Khanda
The 3rd Khanda states about the mind as Brahman. According to this the mind is greater than speech. The mind holds speech and a name. When a man thinks of reading hymns he first reads it in his mind. He would next think and then perform actions. He then thinks in his mind and then has sons and cattle. Thus, mind is the Self, the real Brahman. One must meditate on the mind.

4th Khanda
The 4th Khanda states about the will as Brahman. Will here is considered greater than the mind as man first has the will and then thinks in his mind. Then only he utters his speech and performs his actions. The name includes the sacred hymns and all the sacred hymns are included in the hymns. One who meditates on the will as Brahman reaches as far as the will reaches.

5th Khanda
The 5th Khanda deals with consideration as Brahman. Here consideration (Chitta) is stated to be greater than will. When he considers then only he wills, then he thinks in his mind, he then utters the speech and then performs his actions.

6th Khanda
The 6th Khanda deals with meditation as Brahman. Meditation (Dhyana) is greater than consideration. He who meditates on the meditation as Brahman reaches as far as meditation reaches.

7th khanda
The 7th Khanda deals with understanding as Brahman. Understanding is considered greater then meditation. Understanding helps one to realise the Rig Veda, the Yajur Veda, the Sama Veda and Atharva Veda. It also helps to understand about the epics and the ancient lore, the Vedas, the numbers, Brahma Vidya, the science of etymology, logic, time, ethics, the science of elemental spirits, the science of weapons, the science of serpents, fine arts, heaven, earth, water, fire, air, akasa, birds, trees, herbs, men, gods, righteousness and unrighteousness, truth and false, the pleasant and the unpleasant, the good and the bad etc. One who is aware of this and who meditates on the Brahman attains the worlds of understanding and knowledge.

8th Khanda
The 8th Khanda deals with strength as Brahman. Strength is regarded as greater than understanding. A strong man can defeat a hundred men of understanding. He is able to rise with his strength. The earth, the mid region, heaven, herbs and trees and animals, Cattle, gods and men and everything else stand by strength. One who meditates on the strength as Brahman reaches as far as strength reaches.

9th Khanda
The 9th Khanda deals with food as Brahman. Food is regarded as greater than strength. If a man does not take food for ten days he would become physically weak. Thus, one who meditates on food as Brahman attains the world rich in food and drink.

10th Khanda
The 10th Khanda deals with water as Brahman. Water is regarded as greater than food. When it does not rain sufficiently livings beings are troubled with the thought scarcity of food. When farmers receive sufficient rain they rejoice that it would reap good harvest and there would be no dearth of food. The earth, mid region, heaven, mountains, gods and men, cattle and birds, herbs and trees are all dependent on water. Thus, one must meditate on water. One who meditates on water as Brahman obtains all his desires and remains satisfied.

11th Khanda
The 11th Khanda deals with fire as Brahman. Fire is regarded as greater than water. The fire seizes the air and warms the akasa. When the weather is hot it creates rain. Fire firstly manifests itself that causes rain. When there is thundering and lightening it creates rain. One must thus, meditate on fire. One who meditates on Brahman as fire reaches as far as fire reaches.

12th Khanda
The 12th Khanda states that the akasa as Brahman. The akasa is regarded as greater than fire. The akasa exists in the sun and the moon, lightning, stars and fire. With the help of akasa one calls, hears, and experiences the sense of togetherness. Everything is born in the akasa and also grows in it. Thus, one must meditate on the akasa. One who realises this and meditates on the akasa as Brahman obtains the worlds that extends far and wide free from pain and spaciousness.

13th Khanda
The 13th Khanda deals with memory as Brahman. Memory is considered as greater than the akasa. If people have no memory then he would not be able to hear, think and recognise anything. These activities are possible if they have memory. One should thus, meditate on memory. One who meditates on memory as Brahman reaches as far as memory reaches.

14th Khanda
The 14th Khanda deals with hope as Brahman. Hope is considered as greater than the memory. A person with hope is blessed with memory with which he reads the sacred hymns, performs sacrifices, desires for things. One should thus, meditate on hope. One who meditates on hope as Brahman reaches as far as memory reaches.

15th Khanda
The 15th Khanda deals with Prana as Brahman. Prana is considered as greater than hope. Like the spokes of a wheel remain fastened to the nave, all that begins and ends with hope remain fastened to the Prana. The Prana moves by the Prana.

16th Khanda
The 16th khanda deals with knowledge of the truth. According to it one becomes ativadi by the knowledge of the Truth.

17th Khanda
The 17th Khanda states that truth depends upon understanding. When a person understands the truth then only he declares about the truth.

18th Khanda
The 18th Khanda states that understanding depends upon reflection. Truth can be understood only when it is reflected. Thus, one must desire to understand this reflection.

19th Khanda
The 19th Khanda states that reflection depends upon faith. One can reflect only when one has faith. Hence, one must desire to understand faith.

20th Khanda
The 20th Khanda states that faith depends upon single mindedness. One can only have faith when he has single mindedness. Thus, one must desire to understand single mindedness.

21st Khanda
The 21st Khanda states that single mindedness depends upon concentration. When one practises concentration only then he can possess single mindedness. One must desire to understand the performance of duties through concentration.

22nd Khanda
The 22nd khanda states that concentration depends upon bliss. When one obtains bliss, only then he can attain concentration. Thus, one must desire to understand bliss.

23rd Khanda
The 23rd Khanda state that infinite is bliss and one must desire to understand the Infinite.

24th Khanda
The 24th Khanda deals with the infinite and the finite. When one sees nothing else, hears nothing else, understands nothing else it is the Infinite. However, when one sees something else, hears something else, understands something else it is finite. The Infinite is immortal, the finite mortal.

25th Khanda
The 25th Khanda deals with instruction about the infinite. Sanatkumara explains that the infinite exists below, above, behind, before, to the south, to the north. The infinite exists everywhere. Infinite is also related to the Self. That self is below, above, behind, before, to the south, to the north. One, who understands this, reflects on it.

26th Khanda
The 26th Khanda deals with self knowledge. One who understands the infinite and reflects on it, the Prana, hope, memory, akasa, fire, water, appearance and disappearance, food, strength, understanding, meditation, consideration, will, mind, speech, name, sacred hymns, sacrifice all springs from the Self. A person who has realised this is devoid of any sorrow or grief. It understands the truth, sees everything and obtains everything. He becomes pure minded and is wiped out from the world of darkness.