MAHAVAKYAS

Mahavakyas are great truths stating the oneness of the individual soul, the Atman, with Brahman.  There is a mahavakya in each of the four Vedas:

(1) In the Aitareya Upanishad of the Rig-Veda there is “Consciousness is Brahman” (“Prajnanam Brahma”).

(2) In the Brihadaaranyaka Upanishad of the Yajur Veda there is “I am Brahman” (“Aham Brahmasmi”).

(3) In the Chandogya Upanishad of the Sama Veda there is “That thou art” (“Tat tvam asi”).

(4) In the Mandukya Upanishad of the Atharva Veda there is “This Self is Brahman” (“Ayam Atma Brahma”). 
   
These four mahavakyas are to be understood, meditated upon, and realized.