Yogatattva Upanishad
[4][5] It is listed at number 41 in the serial order of the Muktika enumerated by Rama to Hanuman in the modern era anthology of 108 Upanishads.
[12] As an expounder of Vedanta philosophy, the Upanishad is devoted to the elaboration of the meaning of Atman (Soul, Self) through the process of yoga, starting with the syllable Om.
[18] The term Upanishad means it is knowledge or "hidden doctrine" text that belongs to the corpus of Vedanta literature collection presenting the philosophical concepts of Hinduism and considered the highest purpose of its scripture, the Vedas.
[7] Estimates of the text's origin include those by Michael Whiteman – a professor of mathematics and a writer on Yoga in Hinduism and Buddhism,[19]) who states it is possibly dated to about 150 CE.
A description of pranayama follows, together with the definition of the matra (unit of measurement for the phases of respiration), and important details of mystical physiology (the purification of the nadis is shown by external signs: lightness of body, brilliance of complexion, increase in digestive power, etc.
On Hindu god Brahma's request Vishnu explains that all souls are caught up in the cycle of worldly pleasures and sorrow created by Maya (changing reality).
[32][30] This realization of the supreme self is possible to the yoga student who is free from "passion, anger, fear, delusion, greed, pride, lust, birth, death, miserliness, swoon, giddiness, hunger, thirst, ambition, shame, fright, heart-burning, grief and gladness".
[32][30] In the early verses of the Yogatattva Upanishad, the simultaneous importance of yoga and jnana (knowledge) are asserted, and declared to be mutually complementary and necessary.
[48][47] Laya yoga is presented as the discipline of dissolution where the focus is on thinking of the "Lord without parts" all the times while going through daily life activities.
[46][49] The Laya Yoga, the second in the order of importance, is oriented towards assimilation by the chitta or mind, wherein the person always thinks of formless Ishvara (God).
[52] Thereafter, the Upanishad asserts Raja yoga to be the means for Yogin to detach himself from the world,[53] translates Ayyangar – a Sanskrit scholar.
[54] The tool for meditation, states the text, is Pranava or Om mantra, which it describes in verses 134–140, followed by a statement of the nature of liberation and the ultimate truth.
[55][56] The Upanishad mentions many asanas, but states four postures of the yoga for the beginner commencing on pranayama (breathing exercises) – Siddhasana, Padmasana, Simhasana and Bhadrasana.
The text also states that the yoga student should avoid fasting, early morning baths, sexual intercourse, and sitting near fire.
Milk and ghee (clarified butter), cooked wheat, green gram and rice are foods the text approves of, in verses 46–49.
Kundalini, states James Lochtefeld – a professor of Religion and Asian Studies,[66] refers to "the latent spiritual power that exists in every person".
The five elements of Prthivi, Apas, Agni, Vayu and Akash are called as the "five Brahmans" corresponding to five gods within (Brahma, Vishnu, Rudra, Ishvara and Sada-Shiva), and reaching them is described by the text as a process of meditation.
[68] The meditation on each, asserts Yogatattva, is assisted by colors, geometry and mantras: prthivi with yellow-gold, quadrilateral and Laṃ, apas with white, crescent and Vaṃ, agni with red, triangle and Raṃ, vayu with black, satkona (hexagram) and Yaṃ, akash with smoke, circle and Haṃ.
[73][74] The procedure and benefits of yoga practices of Sirsasana (standing on the head for 24 minutes), Vajroli and Amaroli are explained briefly by the text.
The Upanishad expounds the principles behind Om mantra as part of the yogic practice asserting that "A", "U" and "M" are three letters that mirror the "three Vedas, three Sandhyas (morning, noon and evening), three Svaras (sounds), three Agnis and three Guṇas".
