Introduction to Upanishads
By P. R. Ramachander
"Upanishad means the inner or mystic teaching. The term Upanishad is derived from upa (near), ni (down) and s(h)ad (to sit), i.e., sitting down near. Groups of pupils sit near the teacher to learn from him the secret doctrine. In the quietude of the forest hermitages the Upanishad thinkers pondered on the problems of deepest concerns and communicated their knowledge to fit pupils near them. Sankara derives the word Upanishad as a substitute from the root sad, 'to loosen', 'to reach' or 'to destroy' with Upa and ni as prefixes and kvip as termination. If this determination is accepted, upanishad means brahma-knowledge by which ignorance is loosened or destroyed. Upanishads are found in the concluding sections of Vedas and are classified as Vedanta or the end of the Vedas. There are five Vedas with Yajur Veda having two versions. Each of these five books has several Saaakas (Branches). Each Saaka has a Karma Khanda dealing with the actions to be performed and is made up of Mantras and Brahmanaas. The later deals with Upasana or meditation and has Aranyakas inside them for the benefit of those who have resorted to the quiet habitat of the forest to pursue their spiritual Quest.
The Upanishads are found mostly in the Aranyaka section of the Vedas. The five Vedas have 1180 Saaakas and thus there should be 1180 Upanishads. But what we have now with us is a collection of 108 Upanishads. The list of these 108 Upanishads is given in the Mukthikopanishad.
Out of the 108 Upanishads only 10 have been commented upon by several Acharyas like Adi Sankara. These are Isavasya, Kena, Katha, Aitareya, Brihadaranyaka, Prasna, Mandukya, Taittriya, Chandogya and Mundaka. These have also been popularized by many savants like Swami Vivekananda and Swami Chinmayananda. They all deal with highest category of philosophy and metaphysics. So there is a general impression that all Upanishads are texts of Hindu Philosophy. This is not true. There are Upanishads which even tell you how to wear the sacred ash, how to worship a particular God and so on. But majority of them deal with methods of Yoga and Renunciation (Sanyasa).
Vedas and Upanishads:
"The breakdown among the 108 Upanishads according to the 5 Vedas are as follows:
1. Rig Veda: 10
2. Sama Veda: 16
3. Atharva Veda: 31
4. Krishna Yajur Veda: 32
5. Sukla Yajur Veda: 19
Rig Veda Upanishads :
1. Aitareya 2. Kaushitaki 3. Nadabindu 4. Atmabodha 5. Nirvana 6. Mudgala 7. Akshamala 8. Tripura 9. Saubhagyalakshmi and 10. Bahvracha.
Sama Veda Upanishads :
1. Kena 2. Chhandogya 3. Arunika 4. Maitrayani 5. Maitreyi 6. Vajrasuchi 7. Yogachudamani 8. Vasudeva 9. Mahat 10. Sanyasa 11. Avyakta 12. Kundika 13. Savitri 14. Rudrakshajabal 15. Jabaladarsana and 16. Jabali.
Shukla Yajur Veda Upanishads :
1. Isavasya 2. Brahadaranyaka 3. Jabala 4. Hamsa 5. ParamaHamsa 6. Subala 7. Mantrika 8. Niralamba 9. Trisikhibrahmana 10. Mandalabrahmana 11. Advayataraka 12. Paingala 13. Bhikshuka 14. Turiyatita 15. Adhyatma 16. Yajnavalkya 17. Satyayani 18. Tarasara and 19. Muktika.
Krishna Yajur Veda Upanishads :
1. Katha 2. Taittiriya 3. Brahma 4. Kaivalya 5. Svetasvatara 6. Garbha 7. Narayana 8. Amritabindhu 9. Amritanada 10. Kalagnirudra 11. Kshurika 12. Sarvasara 13. Sukharahasya 14. Tejobindhu 15. Dhyanabindhu 16. Brahmavidya 17. Yogatattva 18. Dakshinamurti 19. Skanda 20. Sariraka 21. Yogasikha 22. Ekakshara 23. Akshi 24. Avadhuta 25. Katharudra 26. Rudrahrudhaya 27. Yogakundalini 28. Panchabrahma 29. Pranaagnihotra 30. Varaha 31. Kalisantaranaand 32. Sarasvatirahasya.
Atharva Veda Upanishads :
1. Prasna 2. Mundaka 3. Maandukya 4. Atharvasira 5. Atharvasikha 6. Brahajjabala 7. Nrsimhatapini 8. Narada Parivrajaka 9. Sita 10. Sarabha 11. Tribadvibhutimahanarayana 12. Ramarahasya 13. Ramatapini 14. Sandilya 15. Paramahamsaparivrajaka 16. Annapurna 17. Surya 18. Atma 19. Pasupatabrahma 20. Parabrahma 21. Tripuratapini 22. Devi 23. Bhavana 24. Bhasmajabala 25. Ganapati 26. Mahavakhya 27. Gopalatapini 28. Krishna 29. Hayagriva 30. Dattatreya and 31. Garuda."
The ten major Upanishads which contain great philosophical discussions and knowledge are:
1. Ishavasya Upanishad
It is one of the great but brief Upanishad. It gives the summary of Indian philosophy very succinctly. It reviews the whole life and comes out with explanations.
2. Kena Upanishad
Kenopanishad derives its name from the first word Kena, meaning â€˜by whomâ€™. It belongs to the Talavakara Bahmana of Sama Veda and is therefore also referred to as Talavakara Upanishad. In short it says that "The One Power that illumines everything and every one is indivisible. It is the Ear behind the ears, Mind behind the mind, Speech behind speech, Vital Life behind life. The ears cannot hear it; it is what makes the ears hear. The eyes cannot see it; it is what makes the eyes see. You cannot speak about it; it is what makes you speak. The mind cannot imagine it; it is what makes the mind think. It is different from what all we know; yet it is not known either. Those who feel they know Him, know Him not. Those who know that anything amenable to the senses is not Brahman, they know it best. When it is known as the innermost witness of all cognitions, whether sensation, perception or thought, then it is known. One who knows thus reaches immortality".
"The Kathopanishad is divided into six Vallis. Valli literally means a creeper. A Valli, like a creeper, is attached to the Sakhas or Branches of the Veda. This Upanishad is also divided into two Adhyayas (chapters) of three Vallis each. "This is one of the most beautiful Upanishads in which the eternal truths are given in the form of a narrative. The narrative is taken from Taittiriya Brahmana (3-11-8) with some variation. The same story is told in the Taittiriya Brahmana, only with this difference that in the Brahmana freedom from death and birth is obtained by a peculiar performance of a sacrifice, while in the Upanishad it is obtained by knowledge only."
4. Aitareya Upanishad
The Aitareya Upanishad is one of the oldest of the Upanishads. It belongs to the Aitareya Aranyaka of the Rig-Veda. It is divided into three chapters and contains 33 verses. The Upanishad deals with the process of creation.
5. Brihadaranyaka Upanishad
"Brihadaranyaka Upanishad means the 'great forest-book'. This Upanishad is one of the oldest of all the Upanishads. It consists of three sections or kandas: the Madhu kanda, the Yajnavalkya or the Muni kanda and the Khila kanda. Here the Brahman is portrayed as universal and undifferentiated consciousness. The doctrine of the indescribability of the absolute and the doctrine of 'Neti, Neti' are explained. This Upanishad concludes by stating the three virtues that one should practice i.e. self-restraint, giving, and compassion."
6. Prasna Upanishad
"In Sanskrit, Prashna mean question. This book consists of six questions and their answers, hence the name. It is in the form of question-answers. Except first and last questions, all other questions are actually a group of smaller sub-questions. As narrated in the beginning of this Upanishad, Six pupils interested in knowing divinity or Brahman come to sage Pippalada and ask questions of great spiritual importance. Pippalada asks them to take up penance of one year. Upon completion of penance, they again come to sage and ask questions, then the sage answers their questions."
7. Mandukya Upanishad
"For the very reason that it explains the esoteric meaning of the fundamental syllable Aum of Hindu spiritual tradition, the Upanishad has been extolled greatly. The Muktikopanishad which talks about all other Upanishads, says that if a person cannot afford to study all the hundred and more Upanishads, it will be enough to read just the Mandukya Upanishad. According to Dr.S. Radhakrishnan in this Upanishad we find the fundamental approach to the attainment of reality by the road of introversion and ascent from the sensible and changing, through the mind which dreams, through the soul which thinks, to the divine within but above the soul."
8. Taittireeya Upanishad
"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."
9. Chandogya Upanishad
"Along with Brihadaranyaka Upanishad the Chandogyopanishad is an ancient source of principal fundamentals for Vedanta philosophy. Considering number of references made to this Upanishad in Brahma sutras, it indicates special importance of this Upanishad in Vedanta philosophy. Important spiritual practices like Dahara vidya, Shandilya vidya, etc. are its speciality."
"This Upanishad begins with an Invocation, praying that eye may see auspicious things, the ear may hear auspicious sounds, and that life may be spent in the contemplation of the Lord. The teaching of this Upanishad is referred to as Brahmavidya, either because it describes first the message of Hiranyagarbha, the casual Brahma, or because the message relates the glory of Brahmam. This Upanishad speaks of Brahmavidya as the mystery which only those with shaven heads and those who go through a rite of having Fire on the shaven head can understand. So, it is called Mundaka, or shaven Head. Apart from this, this Upanishad is honoured as the crest of all, since it expounds the very essence of Brahma Jnana. It is assigned to the Fourth Veda, the Atharvana."
(The write up about the ten major Upanishads has been taken from various web sites. My indebtedness to those great souls is acknowledged.)
The other 98 Upanishads are again classified according to their content as follows.
They are General (of common interest), Saiva (dealing with Lord Shiva), Saktha (dealing with the divine mother Shakthi), Vaishnava (dealing with Lord Vishnu), Sanyasa (dealing with renunciation) and Yoga (dealing with Yogic practices) Upanishads. Though classification is made, still there is some overlapping in the subjects dealt with. Short notes on each of these Upanishads category wise are given below:
General Upanishads (27)
This Upanishad is taught by a sage called Svetasvatara. More emphasis is given in teaching of Sankhya yoga and the philosophy of illusion (Maya).
This Upanishad is by sage Pippalada and deals with the growth of foetus in the womb. It also gives the number of different parts of the body like bones, nerves, flesh etc.
This Upanishad tells us about the penance of a king called Brahadratha. The king asks the sage Sakanya about the feeling of desire in this meaningless world. Sage Sakanya relates him, what has been told to him by sage Maithreya. He teaches him the great science of Brahma Vidya. And tells him finally that mind and illusion are responsible for this contradiction.
This Upanishad is taught by sage Chithra to sage Udhalaka and his son Shwethakethu. It deals about the science of soul. The temporary nature of rituals and good deeds and permanent nature of doing everything without desire is emphasized. It also tells the need for a father to give up all his personality and knowledge to his son and enter Sanyasa.
This is the teaching of Sage Angiras to sage Raikwa. It tries to answer the question of the time and method of creation of the world. It also tries to find out the properties of the soul of beings. And has several aspects of philosophy.
Deals about the properties of Brahmam. Tells that whatever is produced vanishes and then is reproduced. Concludes that the one who knows it well is the Brahman.
Sarva Sara Upanishad
Defines and explains several words like Katha, Bandha, Annamaya etc., which occur constantly in Upanishadic philosophy.
It is an independent text of Hindu philosophy. It tries to investigate what is Brahmam and concludes that the Sanyasi by following proper methods has a better chance of attaining salvation.
Suka Rahasya Upanishad
This Upanishad is supposed to be taught to sage Suka so that he would understand the philosophy of salvation. The explanations of words and ideas are extensive.
This Upanishad investigates and tries to answer the question, "Who is a Brahmin? It says that caste does not come by birth.
Atma Prabodha Upanishad
Tells us about meditation on Pranava and the great Vaishnava mantra "om narayanaya Nama". Defines and tells about the identities of an evolved soul.
Takes a conciliatory stand between Shaiva and Vaishnava. Tells that both are same.
This Upanishad aims at explaining the mantras of the great Purusha Suktham.
This is taught by sage Yagnavalkya to sage Paingala. It gives an explanation of the term â€˜Kaivalyaâ€™. It also attempts to explain the Maha Vakyas of Vedas like â€˜Aham Brahmasmiâ€™ as well the duties of Jnanis.
Tells about the initial creation of the universe starting From Lord Narayana till Lord Brahma. After this there is discussion between sage Suka and the king Janaka regarding the creation of the Samsara. This is followed by discussion of several aspects of philosophy between Sage Nidhaka and his Guru Sage Ripu. It tells that Sastras are burden for a Jnani, Jnana is a burden to those who are attached and so on.
Tells us about the different aspects of the human body, including states of knowledge.
Aksha Malika Upanishad
This Upanishad is taught by Guha to Lord Brahma. It tells us in detail about how to choose the mala (rosary) for use in meditation.
This is an Upanishad which deals with the letter â€™Omâ€™. This is more of a prayer towards â€˜Omâ€™.
Tells us about Surya Angirasa mantra and Gayatri which is a prayer to the Sun. Tells also about the ashtakshara to worship Lord Surya.
Contains the prayer of sage Sankruthi to Lord Surya which contains the Chakshushmathi mantra. This is followed by teaching of Brahma Vidya by Surya.
This is initially taught by Sadashiva to sage Apantharathamas. Tells that There is nothing but Athma and the feeling of existence of others is only illusion.
Tells us who is Savithri and the difference between Savitha and Savithri. Also gives the Savithri mantra.
Deals with various aspects of Athma and how a Brahma Jnani does not see any other thing except Athma.
Kata Rudra Upanishad.
This is teaching of Brahma Vidya by Lord Brahma himself to the Devas. The treatment is philosophical.
Pancha Brahma Upanishad
Details the five stages by which Para Brahman was evolved.
This Upanishad deals with the sarrera Yagna or the sacrifice to the body. Tells what all mantras are to be chanted before taking food. The usual mantras that a Brahmin chants while taking food are contained in this Upanishad.
This Upanishad is the Teaching of Lord Rama to Hanuman. It tells about Vedas, Vedangas and also Kaivalya and also summarizes the Hindu Vedanta. The list of 108 Upanishads is given in this Upanishad.
Saiva Upanishads (13)
In this Brahma teaches the knowledge of Brahmam to sage Aswalayana. Though Adhi Sankara wrote commentaries only for ten Upanishads, he considered this also as an important Upanishad. It deals with the state where the person is himself. The path shown is through meditation and devotion. Keeping the person as the plank and considering OM as the stick which rotates on the plank and gives out the light of fire.
It emphasizes about the greatness of the holy letter "om". It also tells that the form of lord Rudhra is the form of Pranava.
This is taught by Sage Adharva to great sages like Pippaladha, Angiras and Sanathkumara. It emphasizes on the need and benefits on the meditation of the Pranava.
Brahat Jabala Upanishad
This Upanishad is told by Kalagni Rudra to sage Busundi. It deals in detail about the method of preparation of holy ash (Vibhuthi) and method of wearing it.
Kaalagni Rudra Upanishad
It tells in detail about the method of wearing holy ash (Vibhuthi) along with mantras for wearing the same. This is taught by Kalagni Rudra to the great sage Sanathkumara.
Dakshinamurthy is the teacher form of Shiva. He teaches without talking. This Upanishad gives the Dakshinamurthi mantra and the method of practicing it
Sarabha is the animal, man and bird form of Lord Shiva. It is believed that he took this form to control the anger of Vishnu when he took the form of Narasimha. This Upanishad tells about Lord Sarabha.
Tells us lord Shivaâ€™s aspect of Pasupathi (the lord of all living things). Tells how that the entire universe is really one and there is no differentiation.
Rudra Hrudaya Upanishad
Shuka asks his father which God exists in all devas and in which God all devas exist. The answer is this Upanishad. He tells that it is Rudra.
Bhasma Jabala Upanishad
Tells about how Vibhuthi has to be prepared and also the daily duties of a Brahmana. This is the teaching Lord Shiva to Jabala Busunda.
Rudraksha Jabala Upanishad
This is the teaching of Kalagni Rudra to sage Busunda. And deals exclusively about Rudraksha.
Starts with a prayer to Lord Ganapathy and gives the Ganapathy mantra. Tells how worship of Ganapathy is to be done.
Sage Jabali tells sage Pippalada about lord Pasupathi. The need and method of wearing Vibhuti (Holy ash) is given in detail.
Saktha Upanishads (9)
Brahma tells the Devas about who is Sita. He tells them that she is the Adhara Shakthi (the basis which is the foundation) in the feminine form. Tells also about her different forms.
Tripura Tapini Upanishad
Tells about the Sathakshari mantra for meditating on Tripura, the Goddess Parvathy. Several great manthras like Gayatry, and Panchadasakshari are a part of this. Tells about Srividya Upasana.
Sage Rupu tells sage Nidhaka about Devi Annapurna. He also teaches him the Annapurna mantra. This is followed by teaching of philosophical aspects like maya, Yoga and Mukthi.
The Devi tells the devas who she is in this Upanishad. Tells about Panchadasakshari and Navakshari mantras to worship her.
Tells about Sri Chakra and the worship of the devi through the right and left methods.
Tells one important aspect of Sri Vidya Upasana.
Saubhagya Lakshmi Upanishad
Bhagawan Narayana tells about the Shakthi from whom every God originated and teaches the devas, the worship of sowbhagya Lakshmi.
Sarasvati Rahasya Upanishad
This Upanishad is taught by Sage Asvalayana to other sages. He teaches them the ten Saraswathi mantras and methods of worshipping her.
Talks in detail about the existence of Shakthi from whom all gods and knowledge originated. Gives hints of worship of Sri Vidhya.
Vaishnava Upanishads (14)
Describes the principle of Tripath Narayana. It also introduces the Narayana ashtakshara mantra and describes the benefits of chanting it.
Nrsimha Tapini Upanishad
It has two parts. In the poorva part, it tells in detail about the greatness of Lord Naraimha. It also has the great king of Mantras called Narasimha mantra and tells in detail how to meditate on it. In the Uthara part it tells also about the greatness of Pranava and the Narsimha Raja Mantra. It gives detailed method of meditating on Lord Narasimha.
Tripadvibhuti Maha Narayana Upanishad
Brahma did Thapas for 1000 years to know from Lord Vishnu about Brahmam. This is what Lord Vishnu told him. Also clears his doubts such as Brahman having a form and not having a form etc. Also gives the shapes of several yantras.
Rama Rahasya Upanishad
Tells that Lord Rama is Brahma Taraka and expounds various mantras for worshipping him. Also gives yantras for worshipping Lord Rama.
Rama Tapini Upanishad
There are two parts, the poorva Thapini and the second Uthara Thapini. Tells about the greatness of the word "Rama". Tells about the Rama Yantra, which is similar to the Sri Chakra. Tells also the belief that â€˜Lord Shiva tells the Tharaka mantra in the ears of all people dying in Varanasiâ€™ and the method of worship of Rama.
Tells about what is UrdhwaPundra (the sign worn by Vaishnavites) and the rules for wearing it.
Deals about the creation of clearly defined things from that unclear past. Tells how Parajapati came from Avayaktha and went on to create the world. Gives a mantra to worship Lord Vishnu.
Tells about holiness of Kurukshethra, Tharaka mantra and pranava. Tells method of worship of Lord Narayana.
Gopala Tapini Upanishad
Sages approach Lord Brahma to know the procedure to worship Krishna. What he tells them is contained in this Upanishad. The upasana mantra of Govinda is given.
The sages when they meet Rama wanted to embrace him. He made them to be born as Gopis and he took the avatara of Krishna, so that they can embrace him. This book tells as to who were born as what in Krishnavatara.
Brahma tells Narada that whoever meditates and worships Lord Hayagreeva gets to know the Brahma vidya. The mantra for worship of Lord Hayagreeva is given.
Tells the method of meditation and worship of Dathathreya. The Dathathreya mantra is given.
The method of meditation and worship of Garuda, the vehicle of Lord Vishnu is given.
Kali Santarana Upanishad
Tells about how the evils of kali age is to be crossed. The sixteen letter prayer on Rama would help one in doing this.
Sanyasa Upanishads (16)
Tells us about how the great sage of wisdom comes out of all mundane things and lives a life where there is no need for rituals and no differences exist. The mantra for changing Yagnopavita occurs in this Upanishad.
This is compiled by Sage Jabala. This gives more emphasis on mediation and the chanting of Rudra. The greatness of concentrating between the centres of eyes is stressed here.
This Upanishad deals about the teaching of Prajapathi to sage Aaruni. It gives in detail the rules of life to be followed by a Brahmachari and a Sanyasi.
It deals about the discussion between Sage Narada and God on who is a paramahamsa (sanyasi at an advanced stage) and methods to identify him.
It is the teaching of Lord Parameshwara to sage Maithreya. To a large extent, what is given in Maithrayani Upanishad is repeated. In addition God tells to him in detail about his formless form.
Details about the Sanyasa marga involving Nirvana (nudity). Tells about how the people follow it.
Narada Parivrajaka Upanishad
This is the teaching of Narada to the Souunaka Sages. It tells about the methods to attain salvation, the rules to be followed by a Sanyasi, and the time when a person should enter Sanyasa. It also talks about Karma Sanyasa.
It defines the different types of Sanyasi like Kuttesaka, Bahoodhaka, Hamsa and Parama Hamsa .
It is taught by Lord Narayana to Lord Brahma and tells us abut the rules of the life of an Avadhootha.
Tells who can take Sanyasa and what is the procedure.
Paramahamsa Parivrajaka Upanishad
This is taught by Lord Narayana to Lord Brahma. It deals mainly about the procedure of taking sanyasa.
Tells what al things a Sanyasi should posses. And how he should behave.
Tells what is Yagnopavitha as well as Shika, for the sanyasis as well as people of the world. Gives clearly the total length of the Upavitha. For the sanyasi it is the pranava which acts as Yagnopavitha and Shika.
Dattatreya teaches sage Sankrithi as to who is Avadhootha and how he should behave.
The Upanishad tells when to assume sanyasa and also the properties of a sanyasi.
Mind becomes the reason for attachment and salvation. Tells that a real Brahmin should search for Brahmam. Also tells that one taking sanyasa gives redemption for three generation of manes.
Yoga Upanishads (19)
This Upanishad is taught by a sage called Swethaswadhara. More emphasis is given in teaching Sankhya yoga and the philosophy of illusion (Maya).
This talks about meditation on Hamsa mantra and is being taught by sage Gauthama to sage Sanathkumara. The method of meditating on the Hamsa mantra is fully described.
Amrutha Bindu Upanishad
It gives the knowledge of athma in the tasty form of nectar and gives it as briefly as a dot. It tells us about what is Brahmam and other concepts of hard core Hindu Philosophy.
This describes the way and detailed method to chant the holy letter "OMâ€™, which is called here as the nectar like letter.
Kshrika means knife. It is so called because it cuts ignorance using the knife of wisdom. This is a Upanishad which in detail tells about Yoga and its practice.
This Upanishad is the teaching of Lord Paramashiva to his son Subrahmanya. Talks in detail about Yogic practices, defines Chinmathra Swaroopa, Athmanubhava, Jeevan Muktha etc.
Nada Bindu Upanishad
Tells in detail about the meditation on Omkara (pranava). The method of meditation and some problems which may occur are pointed out.
Dhyana Bindu Upanishad
The meditation on Pranava and Ajabha Gayathri is dealt in detail along with the method involved.
Brahma Vidhya Upanishad
Teaches methods of attaining Brahma through meditation. Emphasizes role of Guru. Tells that Sruthi is more important than pramana.
This is the teaching of Lord Vishnu to Lord Brahma. It details out the yogic practice. It also tells about the stages in yoga, defines them and tells how to recognize them.
This is the teaching of Lord Soorya to a Brahmin called Trishiki Brahmana. He clears his doubts about the definition of the body, soul, Karana and yogic practice.
Yoga Choodamani Upanishad
Tells about Yogic practice involving Ajaba Gayatri. Tells about the seats of yoga, tells how to wake up the Kundalani and reach her up to Brahma Randra.
This is the teaching of Sun God to his disciple Yagna Valkya. This deals with the principle of the soul through yogic practice. Definitions of various terms used in Yoga is also given. Tells in detail about Yogic practice and tells us about what is Sambhavi Mudhra.
This is taught by sage Atharvana to sage Sandilya. It deals with Ashtangayoga and Brahma Vidhya.
This is the teaching of Lord Maheswara to Lord Brahma. It deals with subjects like Mukthi, Shakthi, Nadha, Chaithanya and Yoga.
Yoga Kudalini Upanishad
Tells about Kundalani and yogic practice.
This is the teaching of Lord Dattatreya to his disciple sage Sankriti. And tells how the yoga should be done in detail.
Confirms that the knowledge "That this Sun is Brahma" would be realized by chanting of Ajaba Gayathri. Tells what is the merger of mind with Brhama.
Tells about the Brahma Vidya of the body of Varaha. Lord Vishnu as Varaha tells how he should be meditated upon and worshipped. Also deals in detail about the stages of yoga.
1. The classification is modified but based on the writings of Sri Sadagopan in his communication to the Prapathi group.
2. All sentences within quotes are quotations from various web sites dealing with Upanishads.