The Yoga Shikha Upanishad probably originated from the 13th century. This extract from the first chapter perhaps present the earliest known tantric view of Hatha yoga and Raja yoga. This Upanishad is also the oldest text in which the two terms are defined.


Raja yoga described as the union of male semen (Retas (रेतस्, Retas)) with female vaginal secretion (Rajas (रजस्, Rajas)) (YSU I.137).This interpretation of Raja yoga was often literally translated particularly in tantric Kaula (कौल, Kaula) schools. In other tantric traditions, Raja-Yoga (रजयोग, Raja-Yoga) is often translated as the union of Shiva (शिव, Śiva) and Shakti (शक्ति, Śakti), the male and female beings.Modern interpretations of the term Raja yoga usually gloss over these tantric ideas.


Sentence 132

so-.aham-so.-aham-iti prokto mantra-yogah sa uchyate |"
pratitir-mantra-yogach-cha jayate paschime pathi ||132||

सो.अहंसो.अहमिति प्रोक्तो मन्त्रयोगः स उच्यते ।"
प्रतीतिर्मन्त्रयोगाच्च जायते पश्चिमे पथि ॥१३२॥

so-.ahaṁ-so.-aham-iti prokto mantra-yogaḥ sa ucyate ।"
pratītir-mantra-yogāc-ca jāyate paścime pathi ॥132॥

"SO-HAM, I am it, ´I am it´ recited this way is called Mantra-Yoga. |
Through understanding of the Mantra-Yoga the Yogi will be directly born onto the path of liberation. ||132||

sa (स, sa) = he, it
aham (अहम्, aham) = I am
iti (इति, iti) = this way, so
prokta (प्रोक्त, prokta) = announced, exclaimed, recited
mantra-yogah (मन्त्रयोगः, mantra-yogaḥ) = Mantra Yoga
uchyate (उच्यते, ucyate) = is decribed, is called
pratitih (प्रतीतिः, pratītiḥ) = (m.) trust, firm belive in, clear insight into, understanding
mantra-yogat (मन्त्रयोगात्, mantra-yogāt) = through Mantra Yoga
cha (च, ca) = and
jayate (जायते, jāyate) = will be born
paschime (पश्चिमे, paścime) = (loc.) on the west, on the back,
pathin (पथिन्, pathin) = (loc.) path, way, wise
paschime-pathi (पश्चिमेपथि, paścime-pathi) = path on the back, Sushumna, the path to
immortality, the path to liberation, the last birth