Mahāvākyopaniṣad This is one of the minor Upaniṣads and is assigned to the Atharvaveda. There are only twelve mantras, mostly in prose. Parts of this Upaniṣad are identical with the Purusasukta and the Nārāyanopanisad. The fourfaced Brahmā, the creator, is the teacher here. Having found a worthy disciple, he starts teaching this secret and sacred knowledge to him, advising him to give it only to the pure soul, introvert in nature and who pleases the teacher by devoted service. There are two types of people in this world: those who consider this world to be real and those who know that it is not real. The former, entertaining desires and ambitions, take to the pravṛttimārga, the path of Vedic sacrifices and get into bondage. The latter, endowed with the eye of wisdom, take to the nivṛttimārga or the path of renunciation, seek mokṣa or liberation, realise Brahman and become free even here and now. This ātman (inside) which is the same as Brahman, is not darkness but brilliant light. This is realised by the repetition of the Hamsamantra (harhsah so’ham) by identifying the spirit in the sun with one’s own Self. This realisation of the most brilliant ātman/Brahman cannot be compared to samādhi (perfect concentration), yoga- siddhi (perfection in yoga) or manolaya (dissolution of the mind). It is actually an experience of oneness with Brahman. Verses 8 to 10 are identical with the verses 16 to 18 of the Purusasukta and describe the God-vision of the perfected sage. The eleventh verse describes the identity of the light of the sun and the light of the ātman inside brought about through meditation with Praṇava or Om. The last section (12th mantra or verse) gives the phalaśruti, the benefits and results of studying this Upanisad, which is the same as the total destruction of sins and dissolution into Lord Viṣṇu.